Hi Amit,
U can download certificate from the below link
https://academyportalcloud.mendixcloud.com/index.html
Go to exam result section and click on Get Certificate
If you are talking about SSL certificates, you’d normally get this from whoever issued your SSL certificate.
I use DigiCert and if you do too you can find their certificates here…
https://www.digicert.com/kb/digicert-root-certificates.htm
Once you have this, if you are hosting on the Mendix Cloud you can add it using the following instructions.
https://docs.mendix.com/developerportal/deploy/custom-domains/#Uploading
Hope this helps.
Go to https://academyportalcloud.mendixcloud.com/index.html
if you see the Sign In button then click on it
Then you will see 2 section My registrations and My certificates.
Under My certificates double-click on the certificate you want to download. Then go to Exam result tab and click on GET CERTIFICATE.