>Internal parasites can happen at anytime with a tortoise...

Not necessarily. Depends on exposure to eggs of parasites. Captive-bred torts have far less exposure than wild-caught.

>as they have a slow digestive system that it can cause a build up of sugars...

Feeding fruit to a weed-eating tortoise can cause a parasite bloom because the "sugar" is favorable for the growth of some parasites.

>...and it (sugar) can cause parasites.

Sugar does NOT cause parasites; parasite eggs cause parasites.

>So yes just make sure all your homework is done. Good luck!

Indeed! You should.
Russian Tortoise care