Hello Jeya,
Welcome to the Community page,
To turn on MTD if you go to the main cogwheel>account ant settings> advanced> then click on learn how to connect MTD> follow the steps, will take you to HMRC web page fill in the details then it will take you back to Quickbooks. Once back in Quickbooks go to the taxes tab on the main navigation bar on the left-hand side> edit vat>edit settings> fill the information in > save then your ready to do your taxes and submit any returns.