400/800 Times to Walk On at D1 School?

Here is a recent discussion more geared toward starting out with 400’s

In my opinion you would need to improve both your aerobic and anaerobic capacity and almost certainly your technique if you want to progress. It really depends what your ultimate goal is and how much time effort you are willing to commit to the endeavour.

At 250, you are going to need to learn to run well and build up slowly and intelligently or you will probably wreck yourself.