Urrrmmmm....Dorian isn't the Major Scale, that's Ionian...Scales in F are as follows

F Ionian (I Major)
G Dorian (II Minor)
A Phrygian (III Minor)
Bb Lydian (IV Major)
C Mixalodian (V Major, misspelt too)
D Aelion (VI Minor, Relative minor)
E Locrian (VII Minor)

Hopefully that's helped....Contact me if you need more help