As said, there are no validators. At least, not same like in Ethereum. In Bitcoin, when you provide your CPU/GPU power on a pool, you're helping that pool to find a block that its hash is below a certain target. If the pool you're working to, successfully finds such block, you're getting rewarded analogously for the work you provided.

Here's a nice site to learn how it works: https://learnmeabitcoin.com/technical/mining
And one of my previous posts explaining how mining works: Re: How does a bitcoin look like?