Run the following OpenSSL command to generate your private key and public certificate. Answer the questions and enter the Common Name when prompted.
openssl req -newkey rsa:2048 -nodes -keyout key.pem -x509 -days 365 -out certificate.pem
Review the created certificate:
openssl x509 -text -noout -in certificate.pem
Combine your key and certificate in a PKCS#12 (P12) bundle:
openssl pkcs12 -inkey key.pem -in certificate.pem -export -out certificate.p12
Validate your P2 file.
openssl pkcs12 -in certificate.p12 -noout -info