Schedule Breakdown

Hello. I am a recent graduate who is currently working a full time job in tech sales, but I am planning on returning to school to finish my pre reqs (just need organic 2, physics 2, and biochemistry) and study for the DAT. I plan on finding a full time job at a clinic within the next few months. My questions are this:

1. Should I wait to find a clinic job until after I have finished my pre reqs? (Aka would clinic, pre reqs, and DAT all at the same time be too heavy of a workload?)

2. What are the best sources to study for DAT, and what could I do right now to go ahead and start studying before I have a timeline set in place?

3. Suggestions for balancing this workload the best?

Anything helps, and thank you in advance!