Can I remove games that I won on steamgifts and don't became banned?

No. You have to have games you won on your account.

Why? O.o

I hid some games I won. But I am not sure about completely removing them.
Also when I hid them, they are only hidden in library.

Maybe if You ask support to remove this giveaway. But why You want to do this? O-O

Jokes aside, but I think that if you send support a ticket and tell them to check and confirm that you have particular games activated that you want to remove, you shouldn't have problems (you have a proof).

As long as they allow.

The better question is "Why would you enter for games you didn't want?"

View attached image.

Buy the giftable copies of those games and send them to the giveaway creators. Once the giveaway creators pick new winners instead of you, you can delete the games you won from your library.

what do you mean?

Is it me or it actually sounds like this "Can I not activate the games I won on steamgifts and pretend that I deleted them and not get banned?"
No offence op, you have a clean profile but it kinda sounds like this to me.