Online school for grade 3

Anyone else having a really difficult time getting their children motivated to do online school? My son is in grade 3 and so far this online school sucks. I can’t get him to pay attention, he won’t sit still, he doesn’t seem to understand any of it and I’m losing hope. On top of all this I have a 9 month old to look after who always seems to get really cranky when we’re trying to get this online school done with my son.