Plot line graph or geom-line based on three columns and groupby

I want to plot the percentage of people by socio-economic status by AgeGroup. Below is the example of dataframe.

The socio economic status range from 1 to 5 and age group depends upon the age. On x-axis I want AgeGroup and on y-axis I want to plot the percentage of people existing in each AgeGroup by Socio Economic Status.

Below is the example graph I made in excel. Looking for the similar graph in R.

I came up with something along your lines using the tidyverse package:

library(tidyverse)

# create dummy dataset - weight SocioEcononomicStatus sampling for 
#   real world-esque distribution
set.seed(1234)
n_total <- 1001 # number of people
data <- data.frame(S.NO=1:n_total, 
                   SocioEcononomicStatus=factor(sample(1:5, n_total, replace=T,
                                                      prob=c(0.1, 0.3, 0.3, 0.15, 0.05))),
                   AgeGroup=sample(c('18-25', '26-35', '36-45', '46-55', 
                                     '56-65', '66-75', '76-85', '86+'),
                                   n_total, replace=T))
print(data)

# count the number of people in each combination of AgeGroup and SocioEcononomicStatus
data_by_age <- group_by(data, SocioEcononomicStatus, AgeGroup) %>% 
  summarize(n=dplyr::n(), .groups='drop')
arrange(data_by_age, AgeGroup)  # check the raw numbers
# convert to percentages within each AgeGroup
data_by_age <- group_by(data_by_age, AgeGroup) %>% 
  mutate(pct=(n/sum(n))*100)
arrange(data_by_age, AgeGroup)  # check the percentages

ggplot(data_by_age, aes(x=AgeGroup, y=pct, col=SocioEcononomicStatus, 
                        group=SocioEcononomicStatus)) +
  geom_point() +
  geom_line() +
  theme_classic()

There's probably a way to do this in base R, but the combination of the group_by/summarize/mutate functions makes this very intuitive for me.