It's been 5 months since my foot fracture sometimes I get this warm sensation through my foot what causes this?

Nerve involvement? It could have possible nerve involvement.
Swelling. Feet swell during the day normally. After surgery or a fracture, swelling can remain for 6 months to a year.
Hard to know. Anybody that has a foot fracture or surgery, swelling and recovery can last up to a year. It is not uncommon for people to have odd sensations as the bone remodels. The warm sensation is most likely related to the cutaneous (skin) nerves in your foot that are recovering.