Looking for guidance on Ethereum staking options

I’m trying to figure out how to stake my Ethereum properly. I’ve been reading about liquid staking tokens like rETH and it looks like a good option, but I’m confused about the actual process. Where do I purchase these tokens? What’s the most cost-effective method?

I’m pretty new to cryptocurrency so I’d really appreciate a detailed walkthrough if possible. Right now I have some ETH sitting on Robinhood but I want to buy a full coin and put it to work earning rewards. What would be the smartest approach for someone in my situation?