Orgasm & Me...don’t even fit the same sentence😫

I am a 20 year old college student. I have sex however I am not sure about a few things. My nipples don’t tingle when they get sucked on, I don’t feel a rush of climax therefore I highly doubt I have ever came, & what can I do to learn what makes me get there...btw I’m a girl! I just want sex to feel fun and free. I like the person I am with & the package is great plus he is not the first I struggle with I just want to know why anytime I have sex I want it to be over with after 15 minutes. Give me tips to make sex more enjoyable please!!!!!