[Q] Can I get back my HTC Sense 6 on my HTC One M8? topic

So I just installed CyanogenMod on my HTC One M8 and I'm happy with it.
Before I actually did anything I made a full Android Backup and thought that if I ever thought of getting back my stock HTC firmware I would just restore the Android Full backup.
I actually created an extra backup using TWRP.
So the real question here is that how can I get back my stock firmware, and what does the "full Android backup" backup?