Help creating mongo database to use in node/express project

I dont get mongo and how to create a databse in reference to jsons, express and node. I need to create a database of users and comments but dont really get how - Iam not after somebody to do this for me, i am not after somebody to get back to me later

I am after somebody who can. help me with the issues im facing using video caht/screen sharing
I am after somebody RIGHT NOW

if you arent able to follow this, please DO NOT APPLY