MehoyMinoy8 Please test without your mods, as in, move the Mods folder to the desktop and delete localthumbcache.package. You don't need to save your progress, but it's important to find out whether anything in the Mods folder is causing the crashing.
If you get another crash, please provide a dxdiag. Click Windows key-R, enter dxdiag in the run box, wait for the scan to finish, click "Save all information," and save the file to your desktop. From there, you can attach it to a reply using the paper clip (Attachment) icon included with the other formatting buttons.
I can help you move your Mods folder, or the entire Sims 4 folder, to the external drive. But it would be best to fix the crashing issue first.