You can grab a pen that's lying on the desk, but you cannot catch it. Grab and catch do not have the exact same meaning.
Grab = Take quickly, sometimes without asking if is okay. Your hands goes to take the ball directly out of someone's hands.
Catch = To put upb your hands to get the ball that someone throws to you or at you.
Some other uses in English. But I don't know how to say in Korean.
To catch a cold (sickness).
To grab a bite ( to quickly get food and eat).
"잡습니다" means " catch" I had to look it up on the duolingo " lab" section , where you can type a word for Korean translation.