Nonbinary people can use they/them pronouns, or it/its, or neopronouns,
But they can also use he/him and she/her pronouns, and that doesn’t make them any less nonbinary.
Nonbinary people can present androgynously,
But they can also present masculinely or femininely, and that doesn’t make them any less nonbinary.
Nonbinary people can go on HRT and get surgeries to physically transition,
But they don’t have to, and that doesn’t make them any less nonbinary.
Nonbinary people can choose a new name/a different name from their birth name,
But they can also go by their birth name or some variation of it, and that doesn’t make them any less nonbinary.
There are no “rules” to being nonbinary. That’s kind of the whole point. Nonbinary people are nonbinary no matter how they present.