What would be a proper synonym to "make habitable"?

I suggest the word colonize for which Lexico has

colonize
(British colonise)
VERB

1.2 Appropriate (a place or domain) for one's own use.
a small town in a part of the Hudson Valley fast being colonized by weekenders

1.3 Ecology (of a plant or animal) establish itself in (an area)
mussels can colonize even the most inhospitable rock surfaces

So you could say

We are colonising the sea bed and will soon have weekend apartments available.

The colonisation of Antarctica will bring a host of problems with it.

The act of transforming the environment is implicit in the idea of colonisation.