Can you get your CDL license while your class b license is suspended?

If I'm interpreting this correctly, you're asking if you can downgrade a suspended CDL and be able to drive on a regular operator's licence. It does not work that way. While the suspension period on any licence is active, you may not acquire or possess any other class of licence, nor operate a vehicle on any other class of licence.

If you wish to downgrade your CDL, you will have to wait until you have met the criteria to restore your licence and driving privilege, then request a downgraded licence at the DMV once you have done this.