Posting a few missed earlier.

A small tree with huge leaves inside the Conservatory.

I could not get closer but there was a fallen leaf close by.

Can not say. Any Araliaceae member ?

Sorry, I don’t see enough detail to be sure. It could be Araliaceae but possibly other families too- Euphorbiaceae perhaps?

Could be Pachira Species?
Pachira aquatica?
Just a guess.

I do not think so as per images at Pachira aquatica (Cultivated)