Need help with making scatterplots based on two variables in relation to another column

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3

Is this what you mean?

library(tidyverse)

# Your sample data on a copy/paste friendly format, replace this with your actual data frame
sample_df <- data.frame(
  stringsAsFactors = FALSE,
               Sex = c("M","M","M","M","M","M",
                       "M","M","M","M","M","M","M","M","M","M","M","M",
                       "N","N"),
             Month = c("Jaanuar","Veebruar","Marts",
                       "Aprill","Mai","Juuni","Juuli","August","September",
                       "Oktoober","November","Juuni","Juuli","August",
                       "September","Oktoober","November","Detsember","Jaanuar",
                       "Veebruar"),
             Light = c(0.8,2,4.1,6.2,8.9,10.1,9,
                       7.4,4.7,3,1,10.1,9,7.4,4.7,3,1,0.5,0.8,2),
          Molecule = c("BDNF","BDNF","BDNF","BDNF",
                       "BDNF","BDNF","BDNF","BDNF","BDNF","BDNF","BDNF",
                       "Serotoniin","Serotoniin","Serotoniin","Serotoniin",
                       "Serotoniin","Serotoniin","Serotoniin","Serotoniin",
                       "Serotoniin"),
             Value = c(50,80,290,360,570,1120,
                       600,400,280,195,20,500,500,285,378,225,500,136,
                       802,252)
)

# Relevant code
sample_df %>% 
    ggplot(aes(x = Value, y = Light)) +
    geom_point() +
    facet_wrap(facets = "Molecule")

Created on 2021-05-28 by the reprex package (v2.0.0)

Note: Next time please provide a proper REPRoducible EXample (reprex) illustrating your issue.