Server requirement for Running RP Server

I want to running RP Server on FiveM
Imagine I want to have very very much resources(cars,jobs,buildings,Ui,…) means I want to customize my server very much !! add something that other servers don’t have
surely I have to upgrade my server in time , means when I got +50 players I will upgrade server’s hardware , and again upgrade it when I got +120 too again

But please tell me , my server should have what requirements ?(CPU cores , RAM ) ?
when i have ;
0-50 players (x? cpu , x? RAM )
50-100 players (x? cpu , x? RAM )
100-200 players (x? cpu , x? RAM )