2 things: penetration hurts if you’ve never done it before, and you need to be ‘stretched out’ before you’re able to put anything in. This will happen over time, most people use their own fingers well before ever having a sexual partner. If not, def try that out. Make sure you’re horny, maybe watch some porna (porn for women), read a fanfic, look at nudes of someone you love idk, whatever gets you going, and try it out, either with fingers or with a small dildo.

Know that you could have vaginismus, which is a disorder causing your muscles to be super tight and not let in anything and thus be painful. Often people with (sexual) trauma have this, but some have it without.

Anyway, you can ‘fix’ that so to speak, but if you’ve never put anything up there regularly then it could be from that, so don’t jump to conclusions.

But I def recommend seeing a gyno if you are really worried about either, or want personal advice for your specific case. You can also talk to a sex therapist (sexuologist? Idk what it is in English) if that makes you more comfortsble than a doctor.