There are two ways to make canvas prints.
One is to print with an inkjet printer direct onto canvas - which is most common - these are sometimes varnished, sometimes laminated (unless its an epson) and sometimes uncoated (so a wet cloth will damage image).
The second way is to print onto silver based photographic paper, laminate it, then split it (a bit like a beer mat) and laminate onto canvas.
The first method you can set up for a few thousand pounds - the second option, if printing from digital, would set you back £50,000 plus - so it tends to only be available from big labs.