No (or less) fruiting in lemon plant

Question

There is no fruiting in lemon plant and less flowering and flower dropping.

Answer 1

If the flowers are limited and dropping, that would explain why you aren't getting much fruit.
This article should help you identify the underlying cause, and correct it: https://www.gardeningknowhow.com/edible/fruits/lemons/lemon-tree-not-fruiting.htm