Yes, you will get best results if you buy a kit.
I'm not sure where your tile is, but here's a backsplash tutorial: https://www.youtube.com/watch?v=rTRWdIVQ-bU
Yes, but there are so many different types of tile. I would head to your local paint store and ask them what you need based on your particular tile....wall, floor, shiny, slate, porous, shower, etc...and you'll most likely need a sealer of some sort. Especially if it's on the floor.