Hello, @konstantinosm1977,
To solve your issue simply navigate to the Dashboard >> Porto >> Template Builder >> Header >> From there you can edit the header block with the page builder you are using on the site: https://postimg.cc/qg0FD5VM When the editor opens you can simply remove the mini cart widget and save settings. The screenshot is of the Elementor however the process is the same for the WP bakery as well.
I hope you understand and your issue will be resolved.
Best Regards,
PThemes Team.