Knowing how to read guitar sheet music is essential to your growth as a guitarist.
People often look for help in exercises and keep playing the same pieces over and over again not knowing why they aren't getting any better.
The answer lies in the ability to read sheet music properly.
Do you think it's a coincidence that a pro player can read?
Many students of classical guitar remain at just the tab level and then wonder why they're not progressing.
So they try exercises, or getting the latest secret off youtube etc... But nothing really gives any worthwhile results.
They ignore the obvious: they don't know how to read.
It's like wondering why you're not having success as a writer when you don't even know the alphabet.