Can i send a holiday treat box wrapped candy juice boxes and fruit cups and dry milk packs along with cards and letter

If they are in basic training in Illinois, they cant have anything that is food or drink. Open or not. My son just went through basic there.

My grandson just signed up. Is he allowed to have packages from me while in boot camp

In boot camp no they cannot

As long as it hasn't been opened and still have a seal, there shouldn't be a problem.