A closer look
Yes, write is a verb. It means to form letters or words on a surface, like pen on paper. Why not write your ideas on a piece of paper before you start?
Or picture a student in an exam hall, pen moving across the page. He writes his answers clearly so the examiner can read them. Here write is happening right now, in the present.
Don't mix the forms up: the main ones are write, wrote, and written. Writ is an old form you might meet in old texts, but modern English uses written, as in I have written to them already.
There's also a second sense of the verb: to send someone a letter or message, like Please write me when you arrive. That's about communicating with a person, not forming letters on a page, though English uses the same word for both.