Only if you hibernate him. Then he will stop eating on his own about two weeks before he is ready to hide away for winter, which you need to properly store him.
No, there is no reason to “fast” your tortoise or any tortoise really, UNLESS it is prepping for brumation/hibernation..
None of the tortoise care sheets/tabs here on TFO promotes starving a tortoise for a day or two per week. It’s just not natural. Provide a large enclosure, plenty of food & water daily.
Only if you hibernate him. Then he will stop eating on his own about two weeks before he is ready to hide away for winter, which you need to properly store him.