how to set the tab size in vim code example

Example 1: vim change tab size

set tabstop=4

Example 2: vim set tab size

:set tabstop=2 shiftwidth=2 expandtab
:retab

# tabstop		-> Indentation width in spaces
# shiftwidth	-> Autoindentation width in spaces
# expandtab		-> Use actual spaces instead of tabs
# retab			-> Convert existing tabs to spaces