Did you check the basics already?
https://forums.linuxmint.com/viewtopic.php?t=337473
https://forums.linuxmint.com/viewtopic.php?t=353755
https://forums.linuxmint.com/viewtopic.php?t=306195
https://forums.linuxmint.com/viewtopic.php?t=364397
https://forums.linuxmint.com/viewtopic.php?t=283324
https://forums.linuxmint.com/viewtopic.php?t=321939
https://forums.linuxmint.com/viewtopic.php?t=302158
https://forums.linuxmint.com/viewtopic.php?t=340898
https://forums.linuxmint.com/viewtopic.php?t=304942
https://forums.linuxmint.com/viewtopic.php?t=338412
I would also recommend removing/disconnecting all unnecessary storage media from the computer, to make sure the installation only ever focuses on the storage medium, which is important to the installation. This solved a lot of issues for me in the past.