Firefox/Thunderbird export public key

I have imported a .p12 file inside Firefox/Thunderbird, now I would like to export its public key so I can distribute it (without using openssl or whatever command line code), and people can encrypt/verify my signature.

Is it possible to do this only using builtin tools ? ie : from the certificate manager found in Firefox/TB Options > Advanced/Certificates ?

I'm a bit confused with all these different formats :

What I see from this window > your certificates tab, is that I can 'save' my certificate (which outputs a .p12). So both public & private key right ?

Now if I click on "show" for a given certificate, and I go to the details TAB, there is an export button that opens a save dialog with several possible formats (crt, pem, pem-chained, der, pkcs#7, ...). Will this also export the private key ? Or is it safe to export (no private key) to any of these format and distribute the output file ?