Potential Customers list (Names and Mail adresses etc.)

It depends on the reason you want to make this list. Potentially, yes, you can make this list, you can send them a cold email under legitimate interest (the so-called soft-spam) in order to introduce your company and services, but you don't have to insert a call to action because marketing activities require consent as the legal basis.

Here you can find more information on GDPR extraterritorial effect and on consent.

• What is the EU GDPR and why is it applicable to the whole world? https://advisera.com/eugdpracademy/knowledgebase/what-is-the-eu-gdpr-and-why-is-it-applicable-to-the-whole-world/
• Is consent needed? Six legal bases to process data according to GDPR https://advisera.com/eugdpracademy/knowledgebase/is-consent-needed-six-legal-bases-to-process-data-according-to-gdpr/
• Four main questions for obtaining and managing data subjects’ consent under GDPR: https://advisera.com/eugdpracademy/knowledgebase/four-main-questions-for-obtaining-and-managing-data-subjects-consent-under-gdpr/
• Everything you need to know about the GDPR Privacy Notice: https://advisera.com/articles/gdpr-privacy-notice-6-key-elements-to-include/

If you need to understand how to process consent under GDPR, you can consider enrolling in our free online training EU GDPR Foundations Course: https://advisera.com/training/eu-gdpr-foundations-course/