Installation of Sims 3 says Browse to find start disk and disk 1

I am downloading the Sims 3 base game, and in this part of the Installation Guide

{ 7. When, during Installation, the Istallation asks for Disk 1, click 'Browse' and select the
StartDisk you have Mounted. (NOTE: In 'My Computer' or 'Computer' the StartDisk is
called 'SIMS3')
8. When again asked to insert Disk 1, click 'Browse' and select the Disk 1 you have Mounted.}

I go to my computer and it has the F: Drive, with SIMS3 in it. The instructions say to select the start disk but when I click it just opens up a file with .background, Caches, Game, GameData, Installer etc. so I have no idea how to select the start disk without just bringing up the folder every time.

P.S. Im not very smart with computers so please dont use fancy talk aha

what you useing to install the base game if its an iso try daemon tools

Hello,

First, Mount both images.
When the installation asks for Disk 1, click 'Browse' and select óne of
the two Mounted Images. If you get an error, just click the other image
you Mounted. When the Installation asks for Disk 2, do the same. The
Installation should go on now.
If you still don't understand the above, please watch our Installation Video on Youtube: https://www.youtube.com/watch?v=Dm1i-P4I7bc