How can I put the percentage in the Barplot (ggplot2)

Hi, and welcome!

Thanks for including code. It's more useful in the form of a reproducible example, called a reprex. In this case, to answer it it necessary 1) to track down the grid.arrange function (found in the gridExtra package and 2) to guess what data explore_data represents.

The data does not have to be your actual data, just data (preferably from mtcars or another standard built-in data set) that produces the same issue.