New house WiFi setup

Hello,

I have just bought a 3 story house build from thick stone. The WiFi I have currently is slow and will not get to the top of the house. I have 3 children who all use the internet constantly and then we have the added devices such as:
Smart TV’s
Gaming consoles
Tablets
And more I will have forgotten or will add no doubt.

I am after a system that will cover multiple users at once and will reach all over the house.

So far I have seen the Linksys Velop mesh system or place multiple routers over the house.

Can anyone recommend the best way of achieving good signal everywhere that won’t suffer from huge lag when it has lots of users (on avarage 5+ users)

Thanks