I have a 2015 iMac 21.5" that has slowly ground down to crawl. I had this great idea of installing macos on an external SSD (Kingston 2TB) and run it from there instead but no matter what I try I can't get it to work.

At first I downloaded the installer for Monterey but the HDD isn't great and it kept crashing and restarting partway through.

Then I tried installing to the SSD from Recovery (internet recovery wouldn't get past wifi choice so had to use non-internet) but even though the installation went ok it continued to boot from the HDD and in Startup Disk the SSD wouldn't show at all.

Then I made a USB boot stick and did the same steps above with the same result.

The SSD has GUID map and I tried both Mac OS and APFS formatted.

Does anyone have an idea what might be going wrong? Thanks in advance!

I'm not sure if I'm doing this wrong but when I browse Everything I can swipe posts away to hide them. But on my local instance when I swipe I get a message the post is on a remote instance. Is there a way to change this?

I've tinkered with Linux installations before but the last time I made changes to a BIOS it looked 8-bit, not like a windows program (I use Macs, for reference).

I have a Dell Inspiron 5502 (2021) that I just want to remove Windows from and install Batocera for gaming, but I can't figure out how to wipe it.

I'm running Batocera from USB but when I go to "Install on a new disk" there are no targets available. Anyone have any ideas? Thanks!