so a few things about what doc is saying.

First, the master and booster.
If the booster push rod is adjustible, it may be too long and engaging the master cylinder BEFORE you push on the pedal.
to check this, you have to unbolt the master from the booster.
measure the length of the rod coming out of the booster and then measure the depth of the master cylinder.

How I do it is I pull about 3/4 of the fluid out of the master and make sure what is left in it is new so I can see through it.
Powerful flash light. there are 2 holes in the bottom of the master you can see into and watch the piston in the master.
When you unbolt the master and pull away, you can watch for the piston to move. When you push the master back against the booster, you can watch it for movement then as well.
If it moves the rod is too long and you have to move the adjustment to make it shorter.

Second ratcheting.
It is just to engage the parking brake 1 or 2 clicks when you push on the parking brake pedal. enough that it engages the pads to the rotor. before you bleed.