Show Live view when filling up a MetaBox frontend form

Hello,

I have done a frontend Meta Box from for members, that create automatically public posts (after validation | pending).
All data in the populated form can be modified by the member from his dashboard (with Paid Membership Pro).
Now, I like to add a “Live” view on the form's page, when a member fill-up the form - to show to the member how the form pairing (mirror).
e.g., left side of the page with the Meta Box form itself, AND right side of this same page with a Live view automatically updated from the left side.

I really don’t know where to start, because it’s the first time I’m doing this, and I can’t find any article talking about it - because I’m not using the right keywords I suppose!

Any ideas or links to give me a kick? 😊

Thank you,
Eric

Main plugins of this project : WordPress + Oxygen + Meta Box + Paid Membership Pro + Fluent Form Pro + WPCodeBox…