What is true of it
Fdim7 is F, A♭, C♭ and E♭♭ — 1, b3, b5 and bb7 counted from F.
E♭♭ is a double flat, and it has to be: every letter from F upwards is used once, so the bb7 cannot be written any other way.
The easiest of the 1 fingering below is abab: 3 fingers, one of them barring the 10th fret, held at the 10th fret.
None of them uses an open string, so this chord moves up the neck unchanged — the same shape 1 fret higher is the chord a semitone above.
Where its notes are on the neck
The brass dots are F, the root. Everything else is a chord tone with its degree printed in it.
With a different note underneath
Fdim7/A♭
1212
Fdim7/C♭
4545
Fdim7/E♭♭
7878
An inversion is the same chord with a different note lowest. The name changes to a slash name because the bass is what a listener hears as the foundation.