How can I access Raspberry Pi from the internet?

I successfully installed qmi_install and I can navigate through the internet. It is ok!
But I would like to access my Raspberry Pi from the internet , I found his public IP address, but it is impossible to access via ssh. In my local network, it works fine.
Do I have to open a port somewhere in the QMI connection?

The public IP you found probably isn’t the real public IP and you are behind carrier grade NAT (CG-NAT). Unless your mobile provider supports port forwarding or gives you a private IP-address (which is unlikely), you can’t just SSH in. Perhaps a reverse SSH-tunnel using auto-ssh or add-on software can help you.