Hello there, bohadody2005.
Currently, the ability to acquire the VAT certificate in QuickBooks Online is unavailable.
The VAT Registration Certificate is issued by HM Revenue & Customs (HMRC) and confirms that your business is registered for Value Added Tax. You can use this link for more details on the HMRC website: https://www.tax.service.gov.uk/vat-through-software/vat-certificate
You can always revisit this thread if you have additional concerns.