Hi.
The handle was removed by undoing the 4 screws holding the trim and handle. Undo trim first then handle. To re-assemble, do operation in reverse order.
If the glass or the outer frame had came off, there will be more work to do.
I cannot see how bad is the problem. If the glass has slightly moved you can try to put it back in place without removing the door. If the glass is completely out it is better to remove the door releasing hinges and to sit it the whole door on top of a table. If the frame is falling apart the operation may result difficult. You need to strictly observe health and safety.
There are three screws mounted on the door bracket that normally hold the glass in place. In case you have released those screws, place the glass into its holder and get someone to help you holding the glass while you put the screws back in place.
You need to strictly observe health and safety throughout the whole process.
Below the diagram for the oven door. Please click on the picture to enlarge.
Regards.
Ginko.