Formula for calculation ethereum profit?

Hello,

I'm trying to find one place where I can find how to calculate the profit taking into account which GPU is used. Unfortunately, even on ethereum.org, I could not find any info about about that or some formulas that could help me do that.

One of the formulas which I have found was :
Daily Revenue = (hashrate * block reward * block in a day * coin price) / total hash rate
but where I can find info about block reward or block in a day?

On other page, I have found different formula and I do not know which one is better.

EarningsPerMonth = (UserHashMh * 1e6 / ((difficultyTH / BlockTimeSec)*1000*1e9))*((60/ BlockTimeSec)*BlockReward)*(60*24*30)*(EthPrice)

I jus't dont know what my approach should be. I guess correct math would be to calculate how difficult is to mine 1 block using particular hash power (like RTX 3090) but where I can find details about block size for example or block time.