When you sign up to be on my mailing list your email address is stored with the provider Mailchimp. I have access to your email address but will not pass it on to anybody, unless there is some over riding legal reason to do so.
Everyone who signs up does so consensually having gone through a double opt-in process. All newsletter emails have an opt out button and you can opt out at any time. I only collect the bare minimum of information, i.e. your email address
As the mailing list grows it is likely that the list I hold will be segmented in order that I can direct material to people that have the most interest in it. For example, some people may be interested in online tuition and other may not so I would have a separate segment for each group. This is gathered from your responses to mailouts and stored on the email provider’s system. Once again I will never pass this information on. My provider is Mailchimp who are rigorously compliant with GDPR, so your data is also safe with them.