good parenting skills will probably help more than any software will
I know, kind of a smart ass reply no matter how true it is. In any case, I doubt there is a freeware type program to do this, I'm sure any of the commercial programs (Net Nanny etc) would suffice for the simple kinds of things like limiting time/downloads etc.
asus z170-A || core i5-6600K || geforce gtx 970 4gb || 16gb ddr4 ram || win10 || 1080p led samsung 27"