Now I've heard some say that has changed and now you have to download an image for Microsoft and boot from that. You should consult some Windows nerds in one of the online forums. (i.e. reddit, stackexchange, etc.). I'm not an expert and can only report what worked for me.
By the way, your processors are plenty powerful enough to run Windows 11.
If one’s machine is not TPM 2.0 capable and enabled, I don’t think the “live upgrade” will work. Per Dell, some TPM 1.2 machines can be upgraded to 2.0, but, some, including machines that would seem have plenty of RAM, processor, etc., can’t.
In the latter case, the issue can be “forced” with Rufus, but, then there may well be problems with future security updates and so on. Or so I read.
This machine I got for my wife appears to be in the latter category. However, it looks like it needs a big raft of updates from both MicroSoft and Dell, so, I’ll run those and recheck the TPM issue... Assuming we (the machine and I) survive the updates!