Is Prophet Muhammad in Jannah? A Question from a Christian

Assalamu alaikum! I'm a Christian and I'm not very familiar with Islam, but I'm curious about something. I wanted to ask: for Muslims, is it certain that Prophet Muhammad (peace be upon him) and the other prophets are in Jannah (or at least will be on the Day of Judgment)? Or is it something you just don't know for sure, like with anyone else? In Christianity, it's clear that some people are definitely in Paradise-there's no doubt about it. The Bible mentions individuals like Abraham, Enoch, Elijah, and the repentant thief. Catholic and Orthodox traditions also include certain saints, but every Christian denomination agrees on at least those few being saved. I'm wondering if it's similar with Prophet Muhammad and the prophets in Islam, or if even for them, you don't have certainty (even if it's very likely they are saved). JazakAllah khair for your answers, and have a blessed day!