"Warning: Error in : object of type 'closure' is not subsettable: error message

Working on this now! Wanting to understand this, so essentially....

A reprex is a representative example of a coding issue, which essentially is a way to share code I am working on in R on this site.I need to include the data and the code that's causing my trouble.

First I need to use dput() on my dataframe, and then i need to take the minimum reproducible code to share.

I ran dput(head(Jeop3column, 5)[c("category", "question", "answer)]) in my console and that gave me...a bunch of alphabetized data.
In the link the user then included the libraries needed, created a dataframe, and had the problematic part of their code. I would assume I would then need something like this...

library(shiny)

 df <- data.frame(stringsAsFactors = FALSE,
                  category = c(WHAT GOES HERE),
                  question = c(WHAT GOES HERE),
                  answer = c(WHAT GOES HERE)

#PROBLEMATIC PART OF CODE
#printing # correct
    uiOutput("number_correct"),

observeEvent(input$submit_answers, {
        num_right <- 0
        
        if (input$answer1 == single_cat_gen$question[1])
            num_right <- num_right + 1
        if (input$answer2 == single_cat_gen$question[2])
            num_right <- num_right + 1
        if (input$answer3 == single_cat_gen$question[3])
            num_right <- num_right + 1
        if (input$answer4 == single_cat_gen$question[4])
            num_right <- num_right + 1
        if (input$answer5 == single_cat_gen$question[5])
            num_right <- num_right + 1

output$number_correct <- renderUI({
            paste("Percentage correct", "YOU GOT A: ", num_right)

This seems like it is generally the right idea, but I'm not entirely sure, because the questions I have are...
-in the example from the link is someone creating a dataframe using random data? So should I be figuring out 5 corresponding categories, questions, and answers?
-putting the "minimum runable code", does that mean just what I have listed above, as is everything involved with the problem? Or is it every line of code that needs to be run to GET to the problem(in which case would be a LOT more)?
-Am I running what I write in my console? Previously when I ran Reprex I put it at the top of my script, and then when I ran the app it populated the right error message. It says copy your code and then run reprex :: reprex() in the console pane, but I don't really understand that conceptually. That would then make a reproducible example?

No one is usually good at things the first time they do them, and that's likely the case with me here and making a good Reprex. But that's why I can figure the first one out so that going forward I'll know how to do it!

Thanks again,

-Taylor