J’habite means “I live (in)”. It’s not a standalone phrase and should be followed by a geographical location or specific place, etc. Habite is the first-person present tense conjugation of the verb habiter (to live (in)).
Interestingly, you aren’t required to use a preposition with j’habite. So, both j’habite à Paris and j’habite Paris are correct. But it is much more common in contemporary French to use the preposition.
The preposition you use will change depending on the type of place and meaning of the sentence. For instance, you could use j’habite to talk about the city or country you live in, but you might also use it to say something like j’habite dans un appartement. (I live in an apartment).
As a general rule, when using j’habite, the preposition you use with cities/towns/villages is à. The preposition you use with countries varies depending on the gender (and, in some cases, like les États-Unis, the number). For feminine countries, use en: J’habite en France. For masculine countries, use au: J’habite au Canada, unless the country’s name begins with a vowel – then use en. For countries with pluralized names, use aux: J’habite aux États-Unis.
Of course, all of this is useful but with the phrase j’habite you can forego the preposition and just use an article instead. For instance, J’habite la France. This being said, for most contemporary French speakers (at least those from France), this will seem a bit weird or even downright incorrect, so it’s probably best to use a preposition.