aerial root!! nothing harmful or weird about it. i would personally leave it because nature will do what nature does and i like to let my plants do what they want! you CAN cut it if u rly want to, but it’s not necessary and it could stress your plant out to have its root chopped like that.
No you’d need at minimum some stem with it. Preferably a leaf as well. I’m not sure how close to the base of the plant that node is and depending on how much foliage comes after that point it may not be worth it. However if you want to cut that one off but still want to try propagation pothos should have nodes like that under every leaf.