Binding

hello i’m trying to install a m.2 into a Asus Prime B450M-K i don’t have any standoffs or screws and i’m not sure what ones i would need and i don’t have anything that came with the motherboard, it’s just a little hole with no way a screw can be fitted quite confused as this is my first time...

Planning on getting a pretty top notch PC by upgrading old one, piece by piece. So I'd like to know how powerful 120mm fans will do (in CFM)? I guess one would be going in front and other on side panel's lower part, both blowing in?