First time installing master cyl on 01 dodge 1500 when bleeding brakes won't get hard still going to floor what could be the problem

You could be doing it wrong.

Two person mode or one man bleeder?

If a one man bleeder, there is a dvice which will keep the resovour full at all times.

The bleeder is basiccaly a hose, check valve and a container.

You start with the longest line. Open it. Attcach bleeder. Go show to floor a few times and close. Move to next longest etc.

Some master cylinders have two resovours, one for the front and one for the rear. They may have the same fill.

Manually bleeding requires two people. You MUST keep the resovour full. One guy gets at the bleeder screw and opens it while the other guy pushes the pedal and holds.
Then the guy ate the bleeder screw lightly tightens and the guy inside releases. Do this a few times. On the last time turn the bleeder screw to off while the pedal is traveling.

Continue with the same method.

When all done check for air, by keeping your foot on the pedal with constant force. Also try to pump it a few times to get a stiffer pedal.

A bad master cylinder, wheel cylinder, brakes installed incorrectly, parking brake set can all problems.