I was Steam Punk before steam punk was cool. https://www.youtube.com/watch?v=5ZVYajwO42c Still have these, a Stirling engine, and a small manufacturing accessory. Chemistry set, and don’t skimp. Erector set, also don’t skimp. The steam and or Stirling Engine can run what your mind comes up with. For dad/son toys a tether car. https://www.youtube.com/watch?v=DBCs8Nn_2lk
Steam power? Yes.
Chemistry set? I’d guess it’s very hard to find a good chemistry set these days.