Updating Authenticated Origin Pulls cert


I receive an email notifying that we need to update the intermediate certificate before Jan 11.
So, i’m reading this article: https://support.cloudflare.com/hc/en-us/articles/204899617/ but I have a question.

I’m using Nginx, and I have the following configuration:

ssl_client_certificate /etc/nginx/certs/intermediate.crt;

But, in the article, you suggest that we need to use the new certificate origin-pull-ca.pem.

The question is, should I download this .pem file, and just replace it? Or a need to convert this .pem to .crt?

openssl x509 -outform der -in origin-pull-ca.pem -out certificate.crt