To have two left feet means to be a bad dancer.
My husband has two left feet and always treads on mine when we dance together.
Here are some more expressions with the number 2:
two heads are better than one means that it is better to have the advice or opinion of a second person than to do something on one’s own.
I like working with my colleague. Two heads are always better than one.
two of a kind – to be very similar
The sisters are two of a kind. They wear the same sort of clothes and like the same things.
in two shakes – very quickly
I’ll get back to you in two shakes.