Why do people tell me not to get frustrated?

I get frustrated over a lot of things easily and I’ve been called out for it.
My dad was helping me cook and I got very frustrated every time and I was about to throw a fit but, he stopped me quick before I could do so. He said, “Do NOT get frustrated! You need to remain calm and keep trying. You’re not going to get it right the first time. Keep going until you get it right.”
I got frustrated again but he said, “What did I just say! DO NOT GET FRUSTRATED. You do that over every little thing. Stop. Control your anger. You can’t get mad over every little mistake.”
I couldn’t even get mad.
My sister called me out for being frustrated and screaming every time I am wrong. She was trying to teach me to take snapshots. I got angry every time I messes up.
She said, “You better stop getting to frustrated so much. You need to calm down and keep trying. You keep on with that and nobody will wanna help you with anything. Keep going.
She made me keep doing it until I got it right. I got frustrated and whiny but she didn’t respond to it.
I eventually got it right. People make me do things until. I get it right. It’s so tiring.