New roof with ridge vent but no soffit or vents need help!

I have a cape cod house built in 1952. I just bought the house a year ago. The roof was put on 2 years ago with a ridge vent.

In the summer the upstairs is so hot it is unusable. I am redoing upstairs and removed all the drywall and insulation.

I have been reading why it is so hot in there and the key seems to be ventilation. The problem is I have none. There is no soffet or over hang at all and no place for the air to come in.

What can I do??? :?:

I have included lots of large photos below please let them load and check them out

as u can see no overhang :?:

No vent or venting :?:

u can somewhat see the ridge vent

The ? is what can i do i have the room gutted and planed to put up
polystyrene ventilation baffles between the roof rafters to create a path for air to flow up from but i have no soffit or vents what can i do