@dmlebayy First, the easy questions:
- 256 GB is enough for all your Sims 4 content
- It's simple to install the game onto an external drive and slightly more complicated to move the user folder, but it's not difficult at all if you're good at following directions
- Please don't use video guides, which often make the process more convoluted than necessary and might have unwanted side effects; I can link a good written guide if you get this far
- No, you don't need any outside applications, and any guide that says you do should be disregarded entirely
- If you download new packs, they'll be installed into the correct location
- If you download new mods or custom content, you'll need to move the files to the correct location yourself, but this is as simple as dragging and dropping
- The hard drive needs to be plugged in before you open the EA App and through the play session, until you close the App again
- The hard drive also needs to have the same drive letter, in File Explorer, every time you play, or else the App will get confused as to where your game is located
- Windows assigns drive letters in the order in which drives are connected, so if you only have one device that receives a letter (external drives, USB sticks, etc.), you'll be fine
- Origin is dead in Windows
- The EA App will install itself on your internal drive without giving you a choice, which is fine for Sims 4
The more complicated question is whether this is a good idea. Installing Sims 4 onto an external drive only helps with storage, not with a computer that's underpowered in other ways. If you were previously having performance issues that were unrelated to free storage, those aren't going to go away just because the game is now stored externally.
If you'd like, you can post a dxdiag and I'll take a look at your computer's hardware. I can give you a general idea of what to expect. It's also fine to test the game and see what you get, as in, it won't harm your computer provided it can cool itself adequately; no playing in bed with the laptop resting on the covers. But it would be disappointing to buy an external drive only to have it not help you play any better.
