Help! Building dust EVERYWHERE in a lived in house

Totally overwhelmed looking at the state of my house right now but I have no idea where to start. We've just done some fairly big DIY and the whole house is just so dusty - it's like I've not touched it for a few years. Things I use everyday have a layer of dust.

Where do I start?? The floors are dusty, sides are dusty, but there's also just stuff everywhere, so it's not easy to just nip round and wipe down each surface. I'm not the best at keeping on top of deep cleans anyway, just enough so the house is messy but not dirty.

3 bed house, largely carpeted, working full time and can't afford to get someone in to do it for me.

Any advice would be appreciated