Hello, this is quite a common occurrence: you are not alone on this topic.
Before we can get to the matter exactly, there are a few questions one must ask themselves.

1) Have I ever reached “climax” on my own/by myself?
If yes, see question 2.

If no, this may be a good starting point. If you feel comfortable, it may be a good idea to explore your body and see what feels good for you so that you can tell your partner(s). This is great knowledge to
have and share. What stimulates someone to “climax” can also change and evolve over time.

2) How / in what ways, do I stimulate myself to reach “climax”.

3) Am I able to guide my partner, in the same way I stimulate myself, to help me “climax”

  It is important for one to know their own body for what feels good and what does not: everyone has their own erogenous zones. By exploring one’s own body, we are better equipped to guide our partner(s) into honing in on those spots and giving us maximum pleasure to “climax” (orgasm). If you’d like to explore some of your options it maybe of benefit speaking to a sexual therapist or counsellor.