I want a line graph with mean and SD like

Question

I want graph as like as the picture but don't understand how to do this. Actually a have different data for same date how do i made its a line.

library(tidyverse)
library(data.table)
fish <- read_csv(file = "FishF.csv", col_types = cols(DD= col_factor()))
fish1<-fish[is.na(fish)] <- 0
fish
View(fish)
fd<-fish[,c(1,2,3)]
1
newfish <- melt(setDT(fish), id.vars = "DD", 
                measure.vars = patterns("avg","SE"),
                value.name = c("avg","SE"))[ , variable := lvls_revalue(variable, c("C3", "IgM", "IgT", "KHV", "Lyso"))][]
n<-  melt(setDT(fd), id.vars = "DD", 
          measure.vars = patterns("avg","SE"),
          value.name = c("avg","SE"))[ , variable := lvls_revalue(variable, c("C3"))][]