Certified GKH Gardening Expert
Holes in pepper plants and fruit are most often caused be insect pests. There are a few possible culprits here. Pinpointing the right one will help in dealing with it. The most common pests that could cause holes in pepper plants would be slugs, flea beetles, or some type of worm. These articles will help: https://www.gardeningknowhow.com/plant-problems/pests/facts-about-slugs-and-how-to-kill-garden-slugs.htm
You could be sufferfing from a problem called blossom end rot on your peppers. THis is a problem that is caused by a lack of calcium. It is usually caused by to much rain in a short period. Not watering the plants at regular intrevals can cause it also. I hope this helps.