if you don't have a tpm then you need to go ot the bios and look for and option named
PTT and enable it
now try to install w11 again
Intel PTT is basically thefirmware alternative to a the hardware based TPM
It is complicated...
Two Rampage systems. One has a 20 pin TPM socket and the other has the 14 pin one. But no TPM installed. On my Insider Rampage system there are the usual switches for UEFI / Legacy, Fast Boot and several Intel switches for features and virtualization. I have the most current version of Bios but I have not found PTT and will likely not see the TPM option until I get a module. Unfortunately, NewEgg is already sold out on ASUS modules so I will have to check a few other places.
I do not have the Win 11 ISO to install and currently the documentation out there does not like my 6 core i7 processor . So it is possible that one or both Rampage systems will only run Windows 10 when Windows 11 is released. I will probably stay with Win 10 if that happens as there was a significant cost in setting up those systems and at least Windows 10 will be ok to use for a few more years when I will be ready do build something else. It is a decision a lot of PC builders will have to make. It is OK to stay with Windows 10 if it does everything you need it to do. One thing that the enthusiasts are looking at though is the ability to run Android apps as well. They will need to decide if it worth the cost to update.