How do I find my threshold, 5k, 10k and hm pace?

I am utilizing the calendar training option.  What is the definition of warm up?  Do I walk, do I slow jog, do i really need to do this? Also, when the lap changes intervals, is there a way to change the time duration for display?  By the time I feel the interval buzz and my bad eye sight gets focused while running to figure out why my interval is trying to say...I usually don't catch what the display is trying to tell me...

February 25, 2021

• Warm up, 15 minutes. • Run, threshold pace, 15 minutes. • Run, easy pace, 15 minutes. • Cool down, 5 to 10 minutes. • Stretch.