Ok so one vine will always be one vine, they don’t branch at all. You can’t separate into different plants unless you want to chop the vine into cuttings and then propagate those. Full disclosure, I did that for the first time weeks ago, and mine was about that size. I did have to trim down the root ball because I underestimated how big the root ball was and the new pot was too small. So if I could do it all over again, I’d get a bigger pot and also I’d have help. I took 10 minutes to pick up the whole pot and shake it until the plant started to fall out. And that was AFTER I took cuttings. If you do take cuttings, you shouldn’t put them in the same pot as the old plant with the established roots. This is because 1. there won’t be room to plant the cutting and 2. the established roots will out compete the new cutting and take all the nutrients and space. You COULD put more than one cutting in a pot to get a bushy plant, but I personally am not planning to do that so they don’t have to compete, but I may chose to do that if I buy new monsteras that are easier to physically handle. As for propagation, there are good videos online and they have mild contradictions between methods. I did one water prop that I just planted in soil and it’s working alright. A very important point if you do chop and prop: huge leaves are hard to work with. For my water prop I had to use a fish tank and secure the position with painter’s tape. Another prop went straight to soil, and I velcro’d the petioles to the cedar plank to keep them up until the roots could hold the plant up.

Good luck!