In "wants to marry," "to" is part of the infinitive verb "to marry." As for prepositions, you can say "I am married to Vlad," but you can't say "I will marry to Vlad." "Marry to" is incorrect, but "married to" as a condition is fine.

did you mean: 'marry to'? then yes, e.g. She's married to Sam

If you're asking if "marry" can be the object of a preposition, the answer is no. The infinitive is "to marry". "Marry" cannot be a noun. "Marriage" is the noun that may be the object of a preposition.

Absolutely, as in "going to marry," "wants to marry," etc.

Here are typical usages of the verb. In active voice: 1. She married a banker. 2. She got married to a banker. * I believe there's negligible difference in meaning or nuance between the two. * As far as I know, "She married to a banker" is incorrect. In passive voice: - She is married to a banker. ("with" in place of "to" is considered wrong) Others: - in a marriage to/with; in his/her marriage to/with ... (both "to" and "with" seem to be common in these phrases)