I started writing the essay a few separate times without looking at what I had written previously so that each time I wrote it, I wrote from a different angle. Eventually I read everything I had written, and pulled the parts I thought were best. If you think it would be helpful to look at other essays, I don’t think it will stunt your creativity, especially since you’re going to write about yourself and you can’t read that anywhere else.
But you don’t want ‘many’ people looking at your drafts. Choose one or two people who edit well and know your personality to catch any typos and offer up suggestions. If you pick more than that, you’re going to get pulled in too many directions and I think the quality will suffer.
At the end of the day, think of the essay as a chance to explain to schools how awesome you are, and how you’ll be a great physical therapist and an asset to their program. Convey these things in a way that your grades and test scores can’t. Good luck!