If you've never added a certification, you'll first want to add a Licenses and certifications section.
To add Licenses and certifications section and license and certificates:
Click the Me icon at the top of your LinkedIn homepage, then View Profile.

Click Add profile section in the introduction section.
Click Recommended dropdown, then Add licenses & certifications.
In the Add license or certification pop-up window that appears, enter your information into the fields provided.
Click Save.
It should look just like this 🙂
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