Good days!

Could you please help me in selection equipment wi-fi for individual house?
Square house = 12x15=180 meter^2, 2 floors.
I don't have UTP cable inside the house.
And i need seamless wi-fi in all house very good.

Case from ISP located at extension of house.

Are you willing to buy a new router for your house?

Sure, i maybe buy this:

router - HEX PoE - 1 piece.
AP - wAP ac - 3 pieces

Since you don't have and do not plan to put UTP cables, can you take PWR-line AP in consideration?
They can be put in CAPsMAN and i had some very nice results, with having one for each room. They are 2.4GHZ only though.

I planned put the router (HEX PoE) in to technical box at additional house (garage).
The garage has the share wall with house.
The cable UTP go to the 1 AP (wAP ac) from router (HEX PoE) via PoE in garage.
This is AP (wAP ac) at garage should connect via radio to another two AP's (wAP ac) which located at house.
House has a two floor.
One AP is located on every floor.