No space left on PC but still want to use cc

@shoobieloobie  You can definitely install Sims 4 on an external hard drive, and you can move the user files (saves, mods and custom content, etc.) to the external as well.  To be clear, these are two separate steps.  Additionally, if you use more than one external device with this computer, you need to be careful to always connect them in the same order, so the drive with your game data always has the same letter assigned to it.  Windows assigns drive letters in the order the devices appear, so if you switch around the order, the drive letters change too.

You don't necessarily need to do both of the following, depending on how much space you currently have left.  Simply moving the user folder may be enough, and performance will be better if the game's program files (what Origin installs) are on the internal drive.  But in case it's helpful, here are instructions for both.

To move the installed game, first create a new folder on the external drive.  (Call it whatever you want.)  Open your Origin game library, right-click on the Sims 4 icon, select Move Game, and choose the folder you created.  Origin will do the rest.

To move the Sims 4 user folder, you'll need to use a symbolic link.  Please follow these instructions very carefully:

https://crinrict.com/blog/2020/02/moving-windows-documents-folder-to-external-drive-via-symbolic-link.html

It's a good idea to back up your saves elsewhere (e.g. a different external device, or a different folder on this external drive) before doing the above, just in case.

Finally, if you're moving both sets of dats, you'll need to organize the folders on the external drive so that you're not trying to put two "The Sims 4" folders in the same location.  For example, you could make a folder called Games where you move the game's installed files, and another called User Data where you move the user folder with your saves and custom content.