MOSFET Low Voltage Output
Get some logic level FETs

FETs whose drain parameters are specified exclusively at 10V aren't going to be on very far with 5V on the gate, which causes them to not work well at all (or fry).  You need logic level FETs whose drain parameters are specified at 5V gate-to-source, or some low-side gate driver ICs that can swing the gates of your current FETs to 10V, in order to fix that side and get your low-side FETs on all the way.

... and some high-side drivers too

The high-side FETs are a different problem, as their sources will be somewhere near the 48V mark.  This means you need a level-shifting high side driver IC or circuit to turn them on and off from your 0-5V logic signals.  This IC shifts the 0V reference of the signal up to whatever voltage the source of the FET is at, as well as provides sufficient drive to the FET.