Servicenow - Sending file to Mid server

I'm in a project where I need, through MIDSERVER, to fetch a file from a physical server and bring it into my servicenow instance, as soon as MIDSERVER performs this task of bringing this file, I need to create a flow to get this file and look for it in the base to find out if this file exists and if so updates and otherwise create this file in the base.

I would like help first on MIDESERVER and second on building the flow.