Depends on the table you want to modify, and how handy you are...
Will the table still be strong enough after the opening is cut?
Mechanically, it's cutting a rectangle hole, then using a router to cut a small lip for the tempered glass to sit on... NBD. As long as the table is suitable.
You will never get perfect lines with one. A router, jigsaw, or small circular saw is the correct tool with the proper guide. I would rough cut it with a jig saw and true it up with a router.