Although there isn’t much difference between Lineage 14.1 and CM14.1 builds, but the new OS doesn’t fully support root access. On Lineage OS official builds, root access is allowed via ADB only. This wasn’t the case with CyanogenMod ROMs, in cynogenmod we could select root for Apps and ADB or Apps only or ADB only.
I guess This has been done on Lineage OS for security reasons since having root access available for apps is indeed very dangerous for your privacy. A malicious app with root access has the potential to fully control your device remotely with access to ever single file.
Do Checkout Full Tutorial Video:Video Guide by Xtream Droid
The only prerequisites is that you should have is a pre installed TWRP recovery.
Now first you have to download the super su zip file for your device which varies according to your device cpu architecture. But don’t worry i will leave the download link for that in the description box according to the cpu architecture.
Download Link:Download SuperSu File https://download.lineageos.org/extras
The next thing which you habe to do is to boot your device into TWRP recovery for that first switch off your device and by using a specific key combination of power and volume keys you can boot into twrp recovery.
After successfully booting into twrp recovery click on install and navigate the super su zip file and select it. Now just swipe this blue button to right to flash the super su zip file.
After the flashing is done click on reboot to reboot your device it will just take few minutes to boot up your device.Now first go to the root checker app to confirm the root access and as you can see it shows there is no root access. So now we have to enable it from the developer options.
So guys this was a simple method to root your lineage OS if you find if useful the don’t forget to hit that like button.