Q:

how to remove WINDOW OS from another drive?

Here I have two OS in my laptop one Window 10 in C: drive and second is Window 7 in F: drive. When I start my laptop it ask select one OS. So how to remove Window 7 in my laptop without format my F:drive ?

A:

You'll need to remove Windows 7's boot entry, and its system files
Removing boot entry:

Win key + R
msconfig, hit enter
Boot tab
Select Windows 7, delete

Then deleting the Windows directory in your F: drive should get back the space Windows 7 was taking up without reformatting

