The only way to make instant optical color prints from slides is with a Daylab type tabletop printer using Polaroid materials. As Polaroid continues to discontinue films, make SURE you get one that uses an available film. The largest size you are probably going to be able to get an instant print in would be 3 1/4 x 4 1/4 from a film pack. At this moment there do not seem to be any color films from Polaroid left in 4x5. I do not believe there is an available 8x10 Polaroid color material anymore, but I could be wrong. Some vendors still have some in stock, but this method of making 8x10's is very very expensive. Very expensive. like $20 per print I think.
The other way to get "real" prints on Photo paper is to take your slides and negatives to a mini-lab. While the original film will be scanned, the print is a true print on real RA-4 color photo paper exposed by a modulated light beam, and processed in RA-4 color chemistry.