Adding a hyperlink to the checkbox in the contact form 7

It should work like said in my comment but maybe an even better way would be to use the acceptance filed-type that is build especially for that kind of checkboxes.

[acceptance term_and_conditions class:required] I can confirm I have read and accepted the Terms and Conditions.[/acceptance]

contact form 7 edit page go to the tab additional settings and add

acceptance_as_validation: on