Not being able to have children does not prevent someone marrying in the Church. The issue is with actively preventing pregnancy. Which is why NFP is acceptable. NFP was taught in my pre-Cana class 30 years ago and is still taught in my parish. Most of us ignore it, but it’s taught.
As for someone up thread who said most annulments are based on events that happened before the marriage that is not true. Adultery is a valid reason to request an annulment as is abusive behavior or abandonment. A co-worker recently received an annulment because after several years of marriage his wife decided she didn’t want kids after all.