Need to be educated on how to upload files from front end

I am in the middle of writing my own project, I am trying to upload photo's/video's and am having a very hard time getting anything to work properly. My setup: Node/Express Multer to handle server-side Dropzonejs to handle client side Backblaze B2 as cloud storage for photo's Mongo to store data I need to upload these to a cloud object storage called Backblaze B2, however, at this point, I just need to get the files to save on the computer! I am open to changing Multer/Dropzone, I just need a way to accomplish this that makes sense as I have to do a lot of work with photo's in this app. I need someone who is willing to tutor me on how to accomplish this, explain best practices along the way, suggest improvements to performance/security and enjoys teaching. Please have experience with uploading photos to S3 or another object storage. We will need to save the ID's in our database/MongoDB If you are one of these development firms that respond to every gig that comes their way, don't bother asking. I need someone fluent in English that can explain! For those people out there, tell me at a high level how you would accomplish this, the best answer will get the gig! I would assume this will take 2-3 hours to explain the simple things and maybe another 3-4 in the tutoring aspect and providing overall assistance in this effort.