You can't add external RAM to a laptop with soldered memory.

No. That’s not how laptop RAM works. External RAM via USB or Thunderbolt isn’t a thing for system memory—you can’t trick the motherboard into using a stick plugged into a port. Soldered 8GB is stuck 8GB.

Some people bring up “virtual memory” or “swap,” but that’s just using your SSD as a slow crutch when you run out of RAM. It’s not remotely the same as having more physical memory. And no, an external GPU enclosure won’t help either—that’s for graphics, not RAM.

If you need more than 8GB, you bought the wrong laptop. Next time, avoid anything with soldered RAM unless you’re sure 8GB is enough for your whole life.