It's quite possible for 100% loss, has happened to me before. But I'm in a lot of different projects and I don't keep all my assets in one place. I've had farms yield 1000% before so it's a crazy game.
I'm very deep in this space and been doing it a long time, it's not something you are going to just pick up overnight. It's like running a business.
This is the land of software engineers, risk takers, and gray areas. Never put in what you can't lose, and diversify. You aren't getting these insane APYs risk-free - this is kooki stuff. But if you want to dabble, it's quite interesting.
https://staking.synthetix.io/
Then take the minted SUSD and put into Curve for 8%
https://optimism.curve.fi/factory/0
Then take the OP minted and put into XTK pool for another 60%
https://app.xtokenterminal.io/mining/pools/optimism/0xDa62d1...
This in general is known as yield farming