It took me a long time to, but I finally have a couple times. Being with someone I am very comfortable with was essential for me. I’ve never experienced it from penetration alone, don’t be afraid to touch yourself while you’re having sex! So far I’ve only been able to achieve this in positions similar to those I am in when I have explored myself on my own. So far just in missionary. Hope this wasn’t tmi and I hope it helps! Best of luck to you!