Can I create DKIM key using Openssl

I created private and public key using OpenSSL via the following commands

openssl genrsa -out private.key 2048
openssl rsa -in private.key -pubout -out public.key

The Question is:

• Is creating DKIM key (private and public) using Openssl is safe, Is Openssl the preferred tool to do that.
• Can I add the public.key to the domain’s DNS records (TXT).
• Can I used private.key to setup DKIM Signing using Nodemailer.

please provide references in your answer

If the answer to above question is no which other tool should I use to do that? please provide the tool's commands that will generate the DKIM key (private and public)