Она, должно быть, не поняла, по как

Она, должно быть, не поняла, по какой дороге ей идти, и, возможно, заблудилась.

Results (English) 1:

She must have realized for some way to go, and possibly lost.

Results (English) 2:

She must not have realized which way to go to her, and perhaps lost.

Results (English) 3:

It should be, is not realized, on which road to take, and, perhaps, got lost.