@Federico Staiano . Thanks for posting in our Q&A.
From the picture you provided, I notice we are manually request a certificate from a computer and the step is on Certificate enrollment policy. We can select "Active Directory Enrollment Policy" and click next to see if the certificate template is there. If not, we can click "Show all templates" to see if we can see our certificate template and what is the error for this template.
Meanwhile, to request local computer certificate, please follow Nick's suggestion to grant the computer account with read and enroll permission on the certificate template.
Hope the information can help. If there's any update, feel free to let us know.
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