Vim

indent files

align content left

:%le

indent whole file

gg=G

file operations

open file under cursor

gf

open file in new window

CTRL-w f

open file in new tab

CTRL-w gf

tab handling

use expandtab to use spaces instead of tabs

set tabstop=4 shiftwidth=4 expandtab

to convert existind tabs use

:retab

VIM alternative

there is Lapce, which looks pretty good :)