im trying to learn some chords for bass, and I am learning 7 chords, for the chord. And It goes root, flatted 3rd, 5th, flatted 7th. If I am Doing a D minor7 chord how am i supposed to flat a C? do I just make it a B, or keep it as a C? Same with F, do i Make it an E, or Keep it at F?

Bass: Yamaha RBX170
Amp: Fender Rumble 100
Pedal: Boss BOD-3 Bass overdrive pedal