When ever i add the following lines:

ProxyRequests off
ProxyPass / http://localhost:8080/
ProxyPassReverse / http://localhost:8080/

To my conf for my website i get the error listed in the title.

A bit of context on what I'm trying to do is to run a javascript file on my website. This is the js file im trying to run. I found it from a tutorial on youtube and i was interested in trying it out.

const Express = require("express");
const App = Express();

const Keys = ["123", "simplewhitelist"]; 
const secretKey2 = "E);{Q6_<bkrEo;ITBzLfLxTdpMuzSzVIs?}5vyus3l@>+?=>O}uL-(A}M/PJ`w";
const Crypto = require("crypto");
App.use(Express.static(__dirname + '/nodejs'));
function hmac(secret, data){
    const hash = Crypto.createHash("sha512");
    hash.update(secret + data + secret);
    return hash.digest("hex").toString();
};

App.get("/nodejs/checkWhitelist", (request, response) => {
    const Key = request.query.Key;
    const Gamer = request.query.gamer;

    if(Key && Gamer){
        const isKeyValid = Keys.find((key) => key !== null && Key == key);

        if(isKeyValid){
            response.send(hmac(secretKey2, Key + Gamer)) 
        }
        else{
            response.send("Not Whitelisted");
        }
    }
    else{
        response.send("Not Whitelisted");
    }
});

App.listen(8000, () => {
    console.log("App started");
});