We actually start what we call "diversification" (=eating solid food) even earlier in France: we were advised by our paediatrician to do it when the baby was 4 months old.

Apparently if you start early and have him try a lot of different stuff (especially potentially allergenic things like nuts), it causes less allergy problems later on.

It's worked very well for us, the kid loves it and feeding him is quite fun (although certainly messy!)

It's interesting to see how different it is depending on the country though!

My wife and I found this super helpful for introducing foods: https://solidstarts.com/ (no affiliation)

Like, baby oatmeal mixed with breast milk. Then scrambled eggs, soft foods.