You can create an invoice and set it to have a 50% VAT in a few easy steps, @nicolabrown.
You'll need to activate VAT from your account. This should, thereafter, populate automatically on the invoices.
To set up your VAT, follow these steps:
Once done, create a 50% VAT:
You can go back to your invoices page and create a new one. Enter the 50% VAT on the VAT column.
Check these articles for more information:
Please let me know if you have any follow-up questions in creating your invoices, and or other questions. I'm here to help. Have a good one.