Write to HTTPOnly cookie from server in Shiny Application

I want to add/modify HTTPOnly cookies from server.R in R Shiny Application. I've tried session$request$HTTP_COOKIE <- paste0(session$request$HTTP_COOKIE[1], "; t=hello") where "t=hello" is my desired cookie-value pair, but it doesn't work. It prints as result, but doesn't actually add to cookies which can be checked from browser.

library(shiny)

ui <- fluidPage(
  textOutput("cookie"),
  br(),
  tableOutput("table")
)

server <- function(input, output, session){
  
  session$request$HTTP_COOKIE <- paste0(session$request$HTTP_COOKIE[1], "; t=hello")
  
  output$cookie <- renderPrint({
    session$request$HTTP_COOKIE
  })
  
}

shinyApp(ui, server)

Any kind of guideline would be very much helpful.