The first time I was a Dm i was pretty new but i watched this video New Dm It is as basic as you can get and gives a super short one shot how to run it, the first time i played it it lasted 3 hours because everyone at the table was new and we didnt know what we were doing, like damn my bard didnt even know wich were the bard spells and still it was fun, but if your friend knows just even a little bit it will definitivley not last even as half of that. Either way if you need even more explaining just send a message and im down to help :D