New as heck.

Basic info is here
https://www.steamgifts.com/about/faq
Also in this comment
https://www.steamgifts.com/discussion/Q6iD2/how-do-you-know-what-the-cv-of-the-game-would-bring#1T2b80f
you find how calculate levels about levels up and useful links too

Others Useful Links:
https://www.steamgifts.com/about/faq
https://www.steamgifts.com/discussion/RqwrY/contributor-levels
https://www.steamgifts.com/discussion/XaCbA/list-of-all-cv-levels-and-their-corresponding-real-cv
https://www.steamgifts.com/discussions/announcements
https://www.steamgifts.com/discussion/GeDfy/failure-to-activate-and-regifting
https://www.steamgifts.com/discussion/z5iPh/psa-make-sure-the-game-you-receive-is-the-one-promised-to-you

check if winner STEAM user own already the game:
Go to https://steamdb.info/calculator/ write STEAM user name and push enter
At the LEFT side of the page push "GAMES" button\tab under the "information" button
Now enter the name of the game in the search box at the right
Be careful to:
1) NOT push game tab at bottom (that is go to steam page is another)
2) NOT use the UP page search at the start of the page (that is for search in steam db and not in user owned games)

Check users Links for try avoid who cheat:
https://www.sgtools.info/activation (Check if SG user activate all games him win)
https://www.sgtools.info/multiple-wins (Check if SG user win multiple copies of same game)

You don't have to host giveaways, you can just enter for things! But the more giveaways you do, the higher your level will be and the more giveaways you'll have access to. (Theoretically. Most of us don't make giveaways for the higher levels that often.)

Check out the FAQ and you'll find all you need. :)

There's a similar topic made ~16h ago:
https://www.steamgifts.com/discussion/N6ht8/hi-im-new-here
You can already find most info there
And welcome to SG :3

Since wise people already posted the useful (and super important!) information, I am going to cruise in and just say "welcome!".

Cheers!

Edit: You lied, "Heck" has registered 8 years ago! ;D ;D