Welcome to the game

When it comes to advice on paper models, I am afraid I need to ask you a question first. What do you like? Buildings, airplanes, sci-fi, vehicles, ships, etc. I guess pretty much anything you can imagine can be done as a paper model, starting from very simple with just a few pieces to very complicated with thousands and thousands of parts.
My next question would be if you'd be interested in free models (loads of them available, also on these forums, but be aware that there is lots of model piracy going on) which you have to print yourself or models from different publishers that are already printed (ofcourse

) and which can be very expensive.
When it comes to paper, I would suggest DIN A4, but as I have seen in the forums, this can be tricky for people living in the US. So I'd rather pass (especially since I built models from publishers and have no experience with printing my own stuff)
Glue is a theme in itself. But your basic kit should at least include some basic white wood glue. Apart from that I use cyanoacrylat (Sekundenkleber / Powerglue) and for large surfaces a glue with solvents (solvent-free glues are waterbased and make the paper ripple).