If there are two ovens there will be two doors - one large & the other small. They will be made the same - you can practice on the small one.
You can buy a replacement glass panel from an appliance spares place - there are several online outlets.
It will be a good idea to remove the door from the oven and place it on a table or counter - you will only need a screwdriver to replace the glass.
The answer to your question is - Very Easy, April 2015
