Language / What does the conditional/imperative tense mean in Polish? [8]

I am trying my best with some Polish conjugation. I think, although I'm not entirely sure, that the conditional tense is an if/then statement. Let me use the verb to cry as an example. The verb "to cry" (I'm assuming that this is also true to express someone crying, not calling out to someone or something) in Polish is płakać; the conditional tense is płakałabym (if you are female) or płakałbym (if you are male.) The question here is what would that mean in English? Does that mean "I will cry if" or "I would cry."

The imperative is another story. Does that mean a command, like "You do this, or you do that"? The imperative second person is niech płacze. Does that mean, "You cry" like a command?

I'm just trying to clear these conjugations out in my head.