What you have there is just a leaf with petiole. What you need is a section of stem which the petiole was attached to. The petiole and leaf come from a node along the main stem of the plant. That is also where roots come from. A leaf and petiole on their own will wither away.

Thanks for the information @tropicbreezent ! That makes me kind of sad, but at least I didn't have to wait a month to figure it out haha. Much appreciated!

This is what you need to propagate Monstera. A big chunk of stem. I just stuck the lower end in a large pot of soil and in a few months it sprouted. A year later and after a summer outdoors it has about 4 or 5 leaves.

Hello Jasmine.

Did you give it a go and did it grow?