I recently flashed beta flight on my nase with a full erase. During setup my motors run up on me.please help

Right protocol selected for your escs? Escs calibrated and/or min_command, min_throttle & max_throttle set correctly?

Also be aware, there was a bug that made normal pwm esc not work at all, not sure it has been fixed yet.

I guess you installed latest (3.1.5) - maybe also try last stable version (3.0.1) unless you need dshot protocol.