Is this is in the right Thread or should it be in Electronics??
One issue is that you will need another mosfet for the 3rd motor that does not currently have one.If you click "Report to Moderator" at the bottom of your original post, you can ask to have the thread moved to the correct forum. DO NOT create another post.
That arduino board can only supply 15mA current max per pin.Pretty much any motor will draw considerably more than that.check the motors data sheet to be sure.
Thank you for the clarification, I'll go make that adjustment and do some more research.