What is true of it
A11 is A, C♯, E, G, B and D — 1, 3, 5, b7, 9 and 11 counted from A.
On an instrument that cannot reach all 6, the 3, 5 and 1 go first, in that order.
The easiest of the 1 fingering below is 2232: 2 fingers, one of them barring the 2nd fret, held at the 2nd 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.
It leaves out the 3 and 5. 4 strings cannot carry 6 notes, and the 3 is the one this chord can lose without changing what it is.
Where its notes are on the neck
The brass dots are A, the root. Everything else is a chord tone with its degree printed in it.
With a different note underneath
A11/C♯
6775
A11/E
9baa
A11/G
0202
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.