You often have to maintain wheel alignments and rotations that will probably add up to being more than the cost of tyres over the lifespan

Your radiator cap could have failed. It has a spring so if the pressure in the system gets too high it relieves it. That could have failed cause it to release early and your coolant boiled out the top. Alternatively could have an internal leak which will usually present with coolant in your oil or white smoke out your exhaust. There are a lot of options so probably best to have it diagnosed.

If the blend doors are working then the heatercore isn’t getting hot. Either its blocked but that generally would cause the air to not be very hot not no heat at all. Im not familar with the car but I would guess it runs a heater tap that isn’t actuating.