How to run commands inside bash script based on execution

I have a linux bash script which consists of multiple commands. The first time when it runs, it should execute all the commands, and the second time of the execution of the script, it should execute only 2 commands. Can I do this with an "if else" statement?

First time execution of the script: Should run all the commands inside that script Second time execution of the script: Should run only two commands inside that script