Hi @sreford
PayPal Credit is included in the Pay Later functionality that’s implemented in PayPal Payments. But whether you can offer PayPal Credit as a service on your site depends, in parts, on your merchant account eligibility: https://developer.paypal.com/docs/checkout/pay-later/gb/#link-eligibility
This may have changed, but in the past UK merchants had to choose between offering Pay in 3 or PayPal Credit, as it was not possible to provide both at the same time.
But to clarify the requirements, I suggest getting in touch with the PayPal Merchant Support to better understand what it takes to offer PayPal Credit on your site.
The regular Pay in 3 functionality should usually be enabled by default for UK merchants, but PayPal Credit is subject to additional vetting.
I hope this helps!
Kind regards,
Niklas