You need to go to your account settings to claim your certificate. Before you can do so, you also need to agree to the Academy Honesty Pledge.
To make your certificate appear in your profile, you need to have your profile set to public.
Here I kept some of the settings to public to claim the certificates and you can see that freecodecamp mentioned Your certifications will be disabled if set to private
HOPE THIS HELPS
If you have more questions about the certificate the link below might help