You're on a good track, didn't come to mind but prof. Razavi's lectures are great! As the other person mentioned, you can do a lot in simulation. KiCad now has

You're on a good track, didn't come to mind but prof. Razavi's lectures are great! As the other person mentioned, you can do a lot in simulation. KiCad now has a builtin ngspice support (trough it's still a bit rough.) On windows, ltspice is another quite popular free option.