How many lines are in each stanza?

Like lines, there is no set length to a stanza or an insistence that all stanzas within a poem need be the same length. However, there are names for stanzas of certain lengths: two-line stanzas are couplets; three-lines, tercets; four-lines, quatrains.

There can be any amount.

Explanation:

Stanzas don't have to follow a set rule of lines, sometimes varying amounts of stanzas give clues of a deeper meaning in the poem.