How can i get this image onto a normal sized poster?

Do an Internet search for him. There were too many choices to pick one for you when I did the search myself. I just entered his name to find them. I would recommend going to his fan club website so you can buy the poster there. To try to make the poster on your own computer would be too complex for me to explain. You would also need a plotter, which is a very large printer that can print out at that size. You can also print out the poster as 8.5" X 11" tiles, if you know how to do that.