Hello, I see on Elrond bot thatthere is this raffles function but I don't know what it is. Can anyone explain?

Or fake raffle scams

With the bot @ElrondNetwork_Bot sometimes there are raffles, but please watch out for scammers, if anyone messages you pretending you have won it's a scam

Yes

you can claim in v2 of the app which is now live on the play store and the App Store. Please read this medium article fully which explains everything https://legionnetwork.medium.com/legion-super-app-v2-launches-be4bea482a27