How can I be a good student?

I was a good student. I’ve got good GPA, and I was very motivated. However, now, I am a terrible student. During I’ve been little bit depressed, and contracted COVID-19, I didn’t participate to class even via zoom, so my grade become very very worst. College staff said, “We expected you are being excellent student until you graduate. We admitted you to this school because we recognized your potential and motivation, but you quit trying so easily. We are so disappointed.”
What can I do for that they expect it again? I’m feeling overwhelmed by the pressure. How can I be patient against to any pressure and keep to be a good student?