New player with a few questions

Hi everybody :)
New Dota2 fan here, new to genre to be honest and so far i find it really hard and quite enjoyable. I read and watched a lot of guides and even more matches both in game and on youtube. i think i'm getting better but i'm still far from happy with my play. I'm focusing on Support heroes at the moment and although i like playing them i find myself dying an awful lot, like 2-12-16 score at the end of the last match with Crystal Maiden. i think the problem is that i play too aggressively and my positioning kind of sucks, all too often i find myself alone and surrounded by enemy heroes so my map awareness probably also leaves something to be desired :).
Other major problem i seem to have at the moment is item builds, at the end of the match i see other heroes with Vlad's, Sange and Yasha, Shadow Bades,... while i only have Ring of Basilius and a wand. not so much a problem now because i play support so i rather spend my gold on wards but i end up being pretty item poor even when i try to play a carry, any suggestions or does that simply come time and experience? i have to admit i still have to read the descriptions of a lot of items other that starting ones to know what they're good for and i spend some time (too much time really) thinking about what to buy so it might just bee to early for me to shop like Purge :).
I also started playing LoL recently in hope that some of the things i learn there might be applied to Dota and i do think it helped me a little with last hitting or it might just be the practice in Dota finally showing.
Any advice is welcome, i read and reread (and plan to read some of them again) a lot of beginners guides here but i'm pretty sure i could also benefit from some of more experienced players advice and help. If anybody wants to play together sometimes, to teach or to learn together with me please feel free to add me on steam. I'm sure together we can become good :).
Thanks for reading and i knew that all those rumors that Dota community sucks were slanderous. only two matches with real people so far but everybody was super friendly, they were all Carry's but friendly :D. one player even thanked me for healing him even though i was just doing my job, you guys rock

It's a misconception that online gaming community is bad (not only Dota, but every game).
It just looks like that, because the people who write somthing in the chat are mostly flamers. The "friendly" player tend to not write a lot except "gj" or "gg" calls.
The flaming ones are maybe 1 or 2 in a single game (out of 10 players), if there is one at all.

If you want to play carry, practice last hitting. Without that early farm you will get bashed later on. And a support such as CM doesn't really need gold or items, as you already pointed out.

As a support, of course you won't have good items at all, since all the farm goes to the carries. It's good that you buy wards though. Don't forget about the courier and counter warding!

As a carry, you must get farm and kills, your team needs to help you get gold so you can fulfill your role as a carry. They must take care of you and make sure you are farming and you won't die.

Playing League of Legends won't help you, last hitting in that game is piece of cake compared to DotA. In DotA, farming is way harder, not only because the timing but also because the denying of creeps.

Well, since you're already watching videos and reading guides, single advice I can give you is to never give up and ignore the flamers that will say you're a bad player. Even if you win, even if you lose, continue playing and be optimistic. If you're pessimistic and you think you'll lose, then you will, because you will just give up on the game. You must do your best all the time no matter how the game goes, it can always turn around, it's DotA.

Good luck & Have fun :) Any other questions, feel free to ask.

thank you both for answering, i really appreciate it.
since i'm still sticking to playing support heroes (what can i tell you, i like playing support), i always wait for a few seconds at the beginning of the match to see if somebody else will buy him and if not i always grab the courier, and then i buy wards.
i'm new, i mean so new that today was my first real match, i played bots for a while, then i played co-op bot matches to see what it's like playing with real people in the team and from today i'm playing public matchmaking games.
i thought i had some time to learn counter warding seeing how we're noobs playing noobs and i haven't even mastered the observer ward placement but after Riki killed me the 3rd time i realized it's never too early to learn something. i'm not saying i got it down already but i really see the benefits of it even at this early stage. i thnk for efficient dewarding i have to master warding first but i'll keep trying.
I will continue practicing last hitting with bots for when i'm ready to start playing carries in public matches but so far i'm really enjoying support heroes, especially Lich
Also today i got my first gift/treasure "Treasure of the Rogue Knight". i know what it is as i played TF2 but i'm really interested to see what's in there as it's my first one so my question is are the keys exclusively buy only or do they drop in game too? if they don't i'd like to give this one away if somebody needs it. don't get me wrong, i'm not too cheap to fork over €2 for a key it's my birthday tomorrow, Christmas is soon, New Years and i'm a student so any amount of money i spend on a game, even meager one is too much :(. so if the keys don't drop ingame pm me with your steam name if anybody wants it.
One more question, about beta invites. Are they still issuing beta invites? are there any requirements you have to meet to be eligible for them as i never got any? i want to invite a friend of mine, well 2 friends to be honest, they're kind of an item :) to play with me but i never get any invites.
Thank you again for advice, i'm having a really great time learning to play DotA 2 and i still haven't met a single troll. Even if i do someday i still won't care. my view is i'm new and i have the right to learn from my mistakes, nobody should have a problem with that, if anything they could also learn from them.

You need treasure keys to open treasure chests, you can't win them by playing, you have to buy them.

Also, sometimes we receive gift invites, few days ago everyone received 2 more, didn't you receive as well?

no, none so far
i'll just keep playing and one or two are bound to show up sooner or later. maybe it's better that way, i'll be more experienced and i might even be able to teach them a thing or two by then :)

Everyone goes through the noob stage and I'm personally really happy to see someone willing to try and play a Team game with people whom he doesn't know. There are some very very good videos on warding on youtube. Watch the DotaCinema videos on Warding. As for map awareness look at where the creep equilibrium currently is, chances are there are heroes there. If there aren't get back to a tower cuz a smoke gank is likely coming.
If you want something to watch go back and watch DreamHack Winter or watch the ongoing StarSeries. You can learn a lot about Dota by watching, but you have to actively watch. Pay attention to the timing and movement of all the heroes, watch the positioning of everyone: the initiator, the supports, the carry. Look at the items people are buying situationally i.e. Ghost scepters against Clinkz or Phantom Assassin