A starship leaves Earth traveling to a star 1 light year away, max velocity .91 C, accelerating & decelerating 182.5 days ---- how long?

Answer 1

how long what?

sure, theoretically it could accelerate at about 10 m/s²  (you don't want to squash the crew) for half a year and then decelerate that amount for half a year, but you will not have covered a lightyear in that time

Answer 2

You didn't say if speed was immeditate, so the total time cannot be determined.

Also, there would be relativistic effects.