You could save yourself a lot of time by adb sideload magisk.zip from recovery
Make sure you grab the package labeled install files. Otherwise, you won't have the data pre-extracted or have the rominstaller batch file.
Oh I can run fastboot and adb properly thats why I was able to flash lineage recovery and the os but Im just not to sure on where to go from there
*** Disclaimer I am not responsible for any damage you made to your device You have been warned