if earth is 350/365 days in our year, what are the other planets? Help

Obviously I have the length of the years for each planets. I’m trying to set up an orrery program and I’m trying to get a reference on how far into their they are if earth’s jan 1 (1/365) is the “start” of all orbits on the plane. Like if we’re 350/365 then what/687 would mars be? Is there some super obvious formula that accounts for our position/start? I’ve been googling for hours and I’m positive I’m just missing the correct way to ask this question. Please help

edit: I am looking for how I’d find their current positioning if jan 1st is the indexing mark on the plane.

edit: I know that a “day” on other planets is different. I know those values, but I’m not talking about that. Like the percent they have completed their orbits if jan 1st is the beginning point for every orbit.