All English verbs are either active or passive. When a sentence or clause starts with the subject, we use an active verb. For example:
Someone broke the window.
In this sentence, "someone" is the subject, so we use an active verb with it - "broke".
But when a sentence or clause starts with the object, we use a passive verb.
The window was broken.
This sentence starts with the object ("the window") so we used a passive verb ("was broken").
How do we make passives?
Passives are always a combinations of two parts: a "be" verb and a past participle. Don't be confused by the term past participle. A past participle isn't past - that's just its name. We can use a past participle in a past situation, a present situation, a future situation - anything.