First, you want a simplistic way of arranging questions and answers. I personally like to put tables inside tables, and arrange like so:
local questions = {
{StringQuestion,{StringAnswer1,StringAnswer2,StringAnswer3,StringAnswer4},IntCorrectAnswerNumber};
{StringQuestion,{StringAnswer1,StringAnswer2,StringAnswer3,StringAnswer4},IntCorrectAnswerNumber};
{StringQuestion,{StringAnswer1,StringAnswer2,StringAnswer3,StringAnswer4},IntCorrectAnswerNumber};
}
For every question you have a table that contains the following: the question, a table of answers, and the number that identifies the correct answer. Let me break this down.

StringQuestion is your question. It is written as
"Question here"
.

StringAnswer [14] is arranged as table. They are written as `{“My answer 1”,“My answer 1”,“My answer 1”,“My answer 1”}

IntCorrectAnswerNumber is the number that tells what the correct answer is. If your answer is the second option, put
2
. If it is the fourth, put 4
. Same for one and three.
To get random questions without reusing them, do this:
local numberCorrect = 0  Start with 0 correct
local NumberOfQuestions = #questions  Get number of questions
for _ = 1,NumberOfQuestions do  Do this for all the questions
local TempQuestionNumber = math.random(1,NumberOfQuestions)  Get an unused question
local QuestionData = questions[TempQuestionNumber]  Get your question data table (the thing that is {StringQuestion,{StringAnswer1,StringAnswer2,StringAnswer3,StringAnswer4},IntCorrectAnswerNumber})
local Question, Answers, CorrectAnswer = unpack(QuestionData)  Turn it from table into three variables.
 local Question is your question string.
 local Answers is a table of answers. Don't randomize this.
 local CorrectAnswer is the number that is the correct answer.
 For example, you can get the correct answer from the Answers table by doing this:
 local CorrectAnswerAsWords = Answers[CorrectAnswer]
table.remove(questions,TempQuestionNumber)  Make sure question is not reused.
end
local percentCorrect = math.floor(numberCorrect/NumberOfQuestions * 100)  What percent of correct answers you got.
If you have questions about this, ask me! I hope I helped