Hi @ajack just to append to what @stevecook172001 suggested, once you booted into your Lenevo from Live CD / USB in order for Boot-Repair to work, 1st you need to enable community-maintained free and open-source software (universe) from - System> Preferences>Hardware>Additional Drivers
The boot-repair process works flawlessly but if it doesn't work for you then report back , there is another way to get your dual-boot problem fixed .
Slightly related topic
Cheers 