Meaning 'become':
When we use 'get' before an adjective, it often means 'become'.
For example:
I get lost every time I go to New York. It's such a big city.
Even after she took the medicine, her cold just got worse and worse.
He got really angry when she was late for the third time this week.
She doesn't want to get old. She wants to stay a teenage forever.
When we use 'get' with an object + adjective, it means 'make someone or something become'.
For example:
Let's get this show started.
You need to get this room tidy before you go out.