If you would like to enable the student to download the invoice on their purchases,

go to Site > Site settings > Invoice. There is an option 'Enable Download Invoice' under the Invoice Settings.

Once you enable the option 'Enable Download Invoice', the student can download the invoices on their purchase.

By enabling this option, you can enter the Business Name, Address, City, State, Zip Code. Country, VAT ID etc. If you would like to enter any additional details, you can enter in the 'Additional Text' field. All these information will be shown in the downloaded invoice.

It is your decision if you wish to enable the download invoice or not on your site.

The student can log into the site and can download the invoice from their My Account > Billing > Billing History section.

In the similar way, Site Admin downloads the Invoice on their plan purchase