Thanks for posting here, sdfabs-outlook-c.
Yes, you're right. You can process and submit the VAT return through the Taxes menu. We can check if the reason why you can't see it is due to a browser error.
You'll want to open your account using an incognito window and check if you can see it there.
Also, please clear the cache since it causes errors too in QuickBooks Online. Lastly, make sure that the browser you're using is up-to-date.
In addition, make sure that the window isn't zoomed in. That way, you'll be able to see the entire page of QuickBooks Online.
I've added this link for your reference: Submit a VAT return in QuickBooks Online. This will show you how to submit the VAT and will answer most of the commonly asked questions.
Keep on posting here if you need anything else. I'll be here!