Which cooler is best for Intel i7 ?

Check your case size and make sure one of the big air coolers will fit. Noctua is a good choice. They can cost as much as a AIO, I have to say consider and look into an Arctic Liquid Cooler

This guy is the cooler guru on OCNET and this is what he said about it

[Question] Any air cooler tower for a Intel i9-10900K? | Overclock.net

Thank you, I sure will do that. My EATX is huge, won't be a problem, it's just not set up for internal water cooling.

Would you know if a 10th gen processor will work on a Z590 board? I get that I will loose what the 11th gen has to offer but Asus says it will but Intel seems to disagree.

Hemimax said:

Thank you, I sure will do that. My EATX is huge, won't be a problem, it's just not set up for internal water cooling.

Would you know if a 10th gen processor will work on a Z590 board? I get that I will loose what the 11th gen has to offer but Asus says it will but Intel seems to disagree.

It should work, they are on the CPU compatibility list