Hi Paresh,
a box-and-whiskers plot have a well defined five-number summary of your data so in general one should not change the meaning of the box and the whiskers. So by definition a boxplot shows the median not the mean!
In general, you can plot a boxplot in ggplot2 like this:
library(ggplot2)
ggplot(mpg, aes(class, displ)) +
geom_boxplot()

Created on 2020-08-20 by the reprex package (v0.3.0)
(since you did not provide any data or code using an in-build dataset)
What you can do to highlight also the average and the standard deviation is adding that on top of your boxplots. In the first example I use stat_summary that by default calculates the mean and standard error and might be a better choice than standard deviation, but decide yourself - no need to precalculate the stats here). Or you can define the summary stats yourself (2nd example):
library(ggplot2)
ggplot(mpg, aes(class, displ)) +
geom_boxplot() +
stat_summary(color = "red")
#> No summary function supplied, defaulting to `mean_se()`

ggplot(mpg, aes(class, displ)) +
geom_boxplot() +
stat_summary(fun = mean, color = "red") +
stat_summary(
fun.min = function(x) mean(x) - sd(x),
fun.max = function(x) mean(x) + sd(x),
geom = "errorbar",
color = "red",
width = .3
)
#> Warning: Removed 7 rows containing missing values (geom_segment).

Created on 2020-08-20 by the reprex package (v0.3.0)