Limit internet access to 2hours per day

Hey guys,

i would like to restrict the internet access for a person in my family to lets say 2-3 hours per day.
With the poor consumer focused gear i can`t do something like that of course but i was thinking that i will surely be able to achieve a configuration like that with mikrotik gear.

So bascially i want to grant 2-3 hours of internet access per day where the person can freely decide when he uses the time granted. He could spend 1hour at the morning while doing the other 1-2 hours in the evening for example.
If you don`t mind, i would like you to point me in the right direction.
Of course i already did a little bit of research on my own and came up with the idea of purchasing the RB951Ui-2HnD which seems like a good fit for a home wifi router.

I will put the mikrotik behind our existing router and will probably put the exiting one in a locked cabinet or something.
I assume i have to set up a RADIUS server on the RB951Ui-2HnD aka User_Manager and impose limitations on that particular user, am i on the right track here.

Thank you for your kind help.

Dennis