Q.Bell pepper plant
I have noticed groups of little white dots underneath the leaf. I have no clue as to what this is and what could be done about this. I have now removed the leaves infected, but I’m not sure how to prevent it from happening again. I’ve nod spotted any aphids. Please advise. Thanks!

It might be mealybugs or scale. They don't look much like bugs to the naked eye, but rather like spots and cause the same damage as aphids. This article will help if it is that:
https://www.gardeningknowhow.com/plant-problems/pests/mealybugs-white-residue-on-plants-leaves.htm
It could also be powdery mildew or another type of fungus. This article will help with that:
https://www.gardeningknowhow.com/problems/get-the-cure-for-powdery-mildew.htm
At any rate, neem oil will help with both the pest issue and fungus. Here is more information: https://www.gardeningknowhow.com/problems/pests/neem-oil-uses.htm