How much hebrew does the typical jew know?

Hey everyone, I am Jewish but come from a completely secular background but I am curious about religious Jewish life. My question is how much Hebrew does the average non Israeli Jew know? From what I understand, synagogue services are usually entirely in Hebrew. Do people know it like a second language or do they not understand much of it? When they read Torah, do they do it in Hebrew or their native language? For religious Jews who are not near fluent, how do they get through religious life? Do they just not understand what the rabbi is saying? I’m sure this differs depending on denomination and so on, but please break it down for me. Thanks.