Hi there lilothegreat, and welcome to Scarleteen.
There are some things you and your boyfriend can try when it comes to anything that involves vaginal entry, whether that's his finger or a future attempt at having intercourse. First off, he can make sure that his nails are trimmed and filed very smooth, so there aren't any sharp edges to hurt you. It's a good idea to make sure you're already feeling relaxed and aroused any time you're trying something like fingering or intercourse; that's going to make things more likely to feel good. A good water-based lubricant is helpful to have on hand to smooth things out a bit and cut down on friction, too. This article is about intercourse specifically, but a lot of the tips apply to any sort of vaginal entry:
From OW! to WOW! Demystifying Painful Intercourse.
One thing we know about orgasm and how it works is that if you're really stressing out about not being able to reach orgasm, that stress and frustration can actually make it harder for an orgasm to happen. When you're masturbating or being intimate with your boyfriend, it may help to keep the focus on what feels pleasurable to you. Sometimes having general pleasure and enjoyment, instead of orgasm, as your goal during sex can make it more enjoyable and can make an eventual orgasm more likely.
It's common for some people to take a while to figure out what feels best during masturbation or partnered sex, and what helps them achieve orgasm, so if it helps to hear it: what you're experiencing isn't unusual, or a sign that there's something wrong. We have some more information about how orgasms work here, if you're interested in learning more:
Sexual Response & Orgasm: A Users Guide.
Overall, I encourage you not to rush yourself; even if you
want to be ready for something now, if it just isn't feeling right or you need more time, it's better to take things slowly than to push yourself too hard.