"how to create a integer id pk to replace varchar primary key."

Have a database with a varchar primary key. skyandrews said that it will load faster if I create an integer primary key instead. There are several tables relating to the varchar primary key. How can I edit all of the tables to make the database run faster?
here is the database I’m working on:
https://www.dropbox.com/scl/fo/lx6g7fq5vkuy5ehvhp4p7/AAGM7I5_ZKCmlbAKSacBlig?rlkey=dw9w58w8fd0t1fjtfh9tdnn76&st=iz7mhl4q&dl=0