Hello AddYS.

Firstly, welcome to steamgifts :)

I would suggest to read the FAQ and Guidelines.
Please let me draw your attention to the following points:

All giveaways should be for Steam redeemable gifts or Steam redeemable keys.
Beta keys, guest passes, and coupons should not be given away.
Won gifts should be activated to the Steam account used during registration, and they should not be regifted, traded, or sold.

You can find all informations you need about Contributor Level here, here and here.

Useful guides:

• https://www.steamgifts.com/discussion/o6v2O/a-beginners-guide-to-giveaways-winning
• https://www.steamgifts.com/discussion/4tFef/a-quick-overview-guide-of-sgv2
• https://www.steamgifts.com/about/comment-formatting

Giveaway settings
It's a good practice checking the winner's profile before delivering a gift and, if the winner didn't activate some games, or if they won the same game multiple times, you should request a new winner.

If you have more question don't hesitate to ask.

As for your comment here:
No, it's not 50/50. You should not create giveaways if you are not sure that the key will still be redeemable.

All giveaways must be for Steam redeemable gifts or Steam redeemable keys.

Have a nice day.