I already know that gg=G
can indent the entire file on Vim. But this will make me go to the beginning of the file after indent. How can I indent the entire file and maintain the cursor at the same position?
See :h ''
This will get you back to the first char on the line you start on:
gg=G''
and this will get you back to the starting line and the starting column:
gg=G``
I assume the second version, with the backtick, is the one you want. In practice I usually just use the double apostrophe version, since the backtick is hard to access on my keyboard.