The phrase "off to" is commonly used to indicate that someone is about to go somewhere or start doing something. Some synonyms for "off to" include "headed for", "on the way to", "en route to", "bound for", "setting out for", "embarking on", "launching into", "commencing", "starting out", and "beginning". These alternatives can add variety to your writing or conversation, while still effectively conveying the same message. Choosing different synonyms for "off to" can also help to convey a different tone or mood, depending on the situation.