It is very nice that you are in love.
Having questions about sex is totally normal.
Sex is something intimate.
That means: It is only for you and people who you trust.
Maybe your parents are worried that someone might abuse that trust.
But sex is a basic right of all people.
And you have the right to have someone answer your questions.
Think about it: Who do you want to talk to about it?
It could be somebody from your family.
It could be a counsellor.
It could be somebody from school.
Maybe they can give you the answers.
But maybe they do not know the answers.
Then you can ask someone at a counselling center, at no cost.
You can call them or go there in person.
They are very good at answering these questions.
Before you meet them, write down some key words.
That way you won’t forget anything.
Here you will find a list of counselling centers that can help you:
https://www.profamilia.de/themen/sexualitaet-und-behinderung.html
Click on the red sentence “NÜTZLICHE ADRESSEN” (Useful addresses).