It's likely you're thinking of:
"To take a rain check" - This idiom means to politely decline an invitation or offer but express a desire to do it at a later time.
"To take a chance" - This idiom means to risk something in order to achieve a desired outcome.
"To take a stab at" - This idiom means to attempt or try something, especially something difficult.
If you can provide more context or the situation where you heard this phrase, I might be able to help you understand it better.