You should probably start by setting you default units. You can do so by closing all windows but leaving InDesign open. Then choose InDesign (Mac)/Edit (Windows) > Preferences > Units and Increments and setting your units to inches.
The out-of-the-box default unit of measure for ID is Picas and Points (xPy wher the P indicates Picas, and thenumber to thelft is thenumber of picas, and the one to the right is points). If you are comfortable with that system, fine, but you can change the default unit to anything you like by editing the preferences with no files open to affect all new work. If you enter a number into a field without specifying theunits, ID will presume the number corresponds to the default measurement system in place for that field (mostly the ruler units, but scale fileds expect percent), but you can enter any value in any unit as long as you include the unit if measure, and ID will convert to the default units on the fly.
So if your units are set to Picas, and you want to enter 1.528", you would enter 1.528i or 1.528in.
It's using Picas
With no documents open - you should go to Edit>Preferences and change the units to Inches.
Then it will always be in Inches for any new document going forward.