Why is my flask website thats hosted on Virtualbox unreachable to other devices outside of network?

i made a flask website on the virtualbox Virtual machine that i can access on the virtual machine but on other computers i cannot access the website because it says "website is unreachable" ive tried many different ip addressess still nothing is working, any clues why and any solutions? maybe i have to do port forwarding? or i have to allow trafffic of a certain port coz its blocked? i dont know alot about networks.

Also whenever i run my flask website, i notice instead of running at "0.0.0.0" it runs at "10.0.2.15", which is strange coz i set it to run "0.0.0.0" in the code of the flask app, so coz its a virtual machine for some reason its running at "10.0.2.15" which i think is the guest ip address of the virtual machine so maybe thats why the website aint accessible outside the virtual machine.