Hey everyone my step sis wants to know if I can take a pic of her and somehow take her face and put it on one of the princess body? Is that even posible?

with photoshop yes

Won't be as pretty as photoshop, but if you can manipulate Paint and/or PowerPoint those work just as well there's also Pizap.com can give that a try.

There are tutorials available to do so on YouTube with the help of Photoshop.

yes you can with Photoshop I have an ipad and I use artstudio app the best 5 bucks I ever spent! I love that app its how I do all my icons, crossovers, and turn people Disney style