Have a look at different ones and judge it off what your child is like. If they put things in their mouth still, then avoid anything that has small parts. (You can look at age recommendations, but as they won't always be suitable for said child its best to just go by description, etc). I'm going to get the Gabbys Doll House doll house for Christmas
My eldest was passed down a wooden doll house from Le Toy Van from a family friend when she turned 3 and it has been amazing. My now almost 3 year old can spend ages playing and reorganising the furniture and floors and as it can be opened from both sides often play together.
This is for 4+ but I had this exact dolls house when I was very little (I’m now 34!) and it’s still one my favourite memories from my childhood - playing with this dolls house. I’m also aware it’s quite pricey!! https://www.playmobil.com/en-gb/large-victorian-dollhouse/70890.html?gad_source=1&gbraid=0AAAAADpZ-tV0bdeH9zq_yp20Ou8xD5sUa&gclid=Cj0KCQjwrp-3BhDgARIsAEWJ6SxLczpZZqT50jOKWslD8g9MfLbUs_i9f3kf0t3ViXP85OTid5ymT6MaArWJEALw_wcB