Both of you are probably goofing up, but don't let that discourage you.
What you're referring to is a specific type of blowjob called "deepthroating." It's an advanced skill especially if you're new to giving oral. I'll give a few tips to start out with below.
The penis bends but only a very little when it's erect. The angle of the penis in relation to the man's body can change, and it takes experience for the man to adjust to the best angle. When you watch deepthroating in porn usually the focus is on the woman's throat widening as it accommodates the penis.
Deepthroating can happen in a number of positions, but the easiest is for you to be laying on a bed face up with your head hanging off the side of the bed. That aligns your throat the best for his penis to enter.
But BY FAR the first thing to practice is mastering your gag reflex. You have to progressively desensitize it so you don't choke or gag when swallowing his penis. Try starting with a pencil and seeing how far down your throat you can swallow it without gagging. Then move up to larger objects like a small banana (just be sure to put a condom on it so the end can't scratch your throat). But practice with a dildo if you can -- that's the closest to the real thing.
It takes time to learn, but it's extremely worth it!
I hope this helps. I'd post a few instructional links but I'm not sure that's allowed. Feel free to message me though!