What Milling Bits to Buy

Hello, I am new to the community as I receently was able to purchase a Carvera Air 4-axis, and it is coming in the mail. I have some minimal but some experience with CNC'ing through school as I am an engineering student, and I hope to learn more learning with this machine.

Introductions past, I am wondering what bit/mill suppliers people recommend, and also maybe a basic set that I should get in addition to what is shipped with the machine. I know with higher-end machines, bits and mills can get expensive depending on quality because it is worth it. I will mainly be cutting aluminum, mild steel, and PCB boards. I want to stay on the cheaper side, while retaining quality, because I know as a beginner I will no doubt be messing them up, but still want precise parts and tooling that won't be scrap after 2 uses. I know that Carvera has a few kits available, but I don't know if anyone ever uses enough bits/mills to make it suitable, or if the community has any recommendations on manufacturers of others that are more worth the bang for buck.

I am open to learning, and please advise if any more information is needed. Also, any good YouTube channels or online sources to really delve into CNC-precise parts?