My parents never said a thing o gave an explanation of what sex was or how it worked or what the proper names were. They left it to the school I suppose. In school a Jesuit priest gave sex ed of a sorts. He was a sort of wishy-washy guy, nice and all but was far too poetic about things, never using proper words or terms but making up descriptions himself. He wrote a few (approved by the church) books on ‘sex’ and feelings but it was so general as to not really explain much. He later went into a sort of non-political politics, being in the forefront of the early local Green/ecological movement. And ran a sort of commune out in the country where people/teens could go for meditation, sorting feelings out and such. There was supposedly some nudism involved for some.
But luckily, aside from him, I was able to buy English language books on sex in the Belgian city I lived in without any trouble. And if you knew where to go, many were available, all kinds about what were at the time considered sexual ‘aberrations’ like homosexuality, lesbianism, bondage, SM etc. That is where I got most of my explanations from: books.
About the only advice my father ever gave me was ‘for fuck’s sake never get a girl pregnant'. That is why, after coming back from his overseas trips to the Far East or war zones in the merchant marine, he'd give me a big box of expensive condoms (often from Hong Kong, Singapore or Japan/Okinawa.
All he'd say was something like ‘you know how to use these right? Well make sure you do when you need them.’
That was it from my parents, his sexual advice on the avoidance of pregnancy above all things.
Ah yes, and occasional rants about what would happen if I didn't get circumcised (infection, no cure, amputation).
But now that I think about it, he never really used terms like penis/prick/willy or whatever. Just vague roundabout mentioning.