New construction: Choose a ventilation system or integrated window ventilation?

1. Is a ventilation system or integrated window ventilation required according to the usual new building standards today?

2. Or is ventilating several times a day by opening the windows sufficient?

3. In integrated window ventilation, there are passive and active systems, what is recommended?

There is a similar thread on the first page?!

I can't find it right away....

That's why Zaba linked him?!