Let say I am using the E shape Pentatonic scale which I learn it on the 5 fret, and say I use it in the key of G (3th fret) is the finger position still the same? or does all key or root note (E, F, G etc) has there own scale. Can I use all the 5 pentatonic scale in different key but same finger position?
When you learn a scale shape on guitar, the whole lot of it is moveable, provided there are enough frets above or below to accomodate all the notes.
For example, A pent min. basically goes 6 string - 5,8. 5th string - 5-7. 4th string 5-7. 3rd string 5-7. 2nd string 5-8. top string 5 (and 8 if you like). This pattern can be moved up and down, let's start on 6th string 3rd fret. Copy the exact fingering, (take 2 away from each fret number) and you have G pent min. Start at fret 8 (add 3 to each fret number) and you have C pent min.
This works for each and every scale you can play. Learn, say, C harmonic min. starting on fret 8 on bottom string. Start instead on 6th fret, and you'll be playing Bb harmonic minor, assuming you use the same finger pattern, relatively.
Be aware that there are two common pentatonic scales - minor and major, so just calling something 'pentatonic' is a bit open, although I guess a lot of guitarists, beginners in particular, will be meaning pent. minor.
Thanks for your question. Tim's answer is 100% correct.
Another way to answer would be yes - all of the patterns remain the same for a given type scale - regardless of where you start the pattern on the neck (which will determine the key of the scale you are playing).
If you have studied the CAGED system, you may have learned that the pattern shapes are based on the open position chord shapes for major chords in standard tuning. You have the C shape, the A shape, the G shape, the E shape and D shape. Those are the 5 chords that can be played as open chords. Any other major chord is played as a barre chord using one of those 5 shapes. For example an F Major chord is an E shaped chord with either a full bar or a mini bar playing only the top four strings and a B flat in first position is an A shaped Barre chord (which can also be played using only the top four strings).
By using a barre, you can play any chord using any one of these 5 shapes somewhere on the neck.
When you move a barre chord up and down the neck, the shape stays exactly the same. For example if you play an E shaped barre chord on the third fret to play a G - the shape stays exactly the same if you move it up to the fifth fret to play an A.
The same concept applies to scale shapes. The shapes stay exactly the same no matter where you start. Works that way on guitar but not on keyboard.
Hope that helps you understand the concept of movable scale patterns and movable barre chords. Keep up your interest in learning to play your instrument better and better as you go by increasing your understanding of the theory and concepts that will make it easier to expand your capabilities.