Bike repair help

Hoping I can ask here as I cant find the answer online.. When i use the back brake it doesnt release from the wheel rim. Ive identified either my handbrake not springing back properly (it doesnt spring back when released) , cable issue (i can manually pull the calipers apart releasing the brake) or caliper spring issue.

My question: i made an appointment at a shop but the next available was late june. Can i use only the front brake until its fixed?

I feel like it may be a lot for me to try to fix as a new rider. Im going back to work monday and was hoping to commute in. Thanks!