I assume you are talking about a split leaf philodendron.
I would put this into a pot large enough to contain the roots that have grown without crowding them. A gallon would probably be the minimum if it’s a decent sized cutting.
Use fresh, new potting soil, not garden dirt or soil from another pot. Used soil can contain all sorts of pathogens and seeds you don’t want on y our new plant.
Be aware that most house plants LIKE to have fairly crowded roots to do well. That doesn’t mean stuff it into a tiny pot, it means more than as your newly rooted baby makes roots and gets established, you won’t see much top growth because the energy will be going into the roots. Once the roots are well established it will start growing out the top.
So...plant it in a pot that is big enough to not crowd the roots, then don’t mess with it again for a long time and when you do need to repot it, go up only a little in your pot size, like an extra inch all around.
I once repotted all my plants into much too big of pots, then waited a year or more to see them do ANYTHING. After two or three years they were all happy and growing madly again, but they had to fill up their pots with roots to get happy first.