PuppeteerTwitter.js

function followBot(params) {

    return new Promise(async (resolve, reject) => {
        const browser = await puppeteer.launch({headless: false});
        const page = await browser.newPage();

        await page.goto('https://mobile.twitter.com/login');

        await page.waitFor('[name=\'session[username_or_email]\']');
        await page.$eval('[name=\'session[username_or_email]\']', (el, params) => el.value = params.username, params);
        await page.$eval('[name=\'session[password]\']', (el, params) => el.value = params.password, params);

        await page.$eval('[data-testid=\'LoginForm_Login_Button\'', el => el.click());
        await page.waitFor('main');

        const accounts = fs.readFileSync("targets.txt", "utf8").split("\n");

        for(const account of accounts){

            console.log("Following " + account);

            await page.goto('https://mobile.twitter.com/' + account);
            await page.waitFor('.css-18t94o4');

            await sleep(1000);

            await page.$$eval('div', (elements) => {
                return new Promise(async (resolve, reject) => {
                    elements.forEach(f => {
                        if (f.getAttribute("data-testid") && f.getAttribute("data-testid").indexOf("follow") > -1) {
                            f.click();
                        }
                    });

                    resolve(true);
                });
            });

            await sleep(5000);
        }

        resolve();
    });
}