Do you have bios access or a way to boot from USB? That's probably going to be required, and the system might be locked down to prevent that. Also SecureBoot might cause you problems. I am unsure if endeavorOS supports secureboot out of the box. (And whether it requires installing a key into UEFI).

Your speed limitation is probably going to be whatever bus its hooked to. USB? What version of USB? You can look up USB bus speeds online. Note that there are sometimes more than one USB bus on a system, you should use the highest version your devices will both support with the least amount of devices plugged into it.

At the end of a day, Linux will run off of some very very old and slow equipment, so its probably going to work even on USB-2. Performance may be subpar depending on whatever its hooked up to. Linux can work well, even in these scenarios, and depending on what you are doing, there are even ways to make it faster, but some of them also move you farther from maintainability, which for someone who is less experienced with Linux, could cause endless heartache. "Just because you can, doesn't mean you should". Try to keep it simple and just try and see. Worse come to worse, you learn some things and just remember that Linux is going to do whatever you ask it to, even if its the wrong thing. Its not going to protect you from yourself like windows or macos would, but its also going to run on a toaster oven if you utter the right incantation, unlike macos or windows.

The user learns and customizes linux themselves. MacOS is unknowable magic which forces you to do things a certain way, and Windows is like a fisher price toy with 3 buttons all of which make noise and make lights, but nothing really happens in the end, at least not unless you take the batteries out, put them back in 3 times, and flip it upside down and click through 17 pop up buttons that appear whenever you are busy trying to actually do something. (Sorry, I ranted again)