As P. Phillips has mentioned, once your email address is "sold," there's not much you can do about stopping SPAM.
I do have a suggestion for you. Since you are using a Mac, you should have an Apple ID, which provides you with an iCloud email account. Use this account as your primary email address. However, only provide this address to people you know (and trust). You shouldn't need to use it for any of your other correspondents. You can certainly keep your BellSouth account.
Now to keep SPAM reaching your inbox, I further suggest that you do, at least, the following two things:
- Open a new email account on a free email service that provides SPAM filtering. Two good choices would be Google's Gmail and Microsoft's Outlook/Live/Hotmail services. Use those service's SPAM filtering tools to be the "first line of defense" against SPAM messages. Also configure that service to forward the filtered messages to your "main" iCloud account. The key here is to provide these addresses to your "casual" people contacts, or businesses. Any email you receive from them will first get filtered ... and, only if they meet your filtering criteria, will they be forwarded.
- Employ the use of a dedicated SPAM-filtering app, like SpamSieve. This will be your "second line of defense." With this app, any emails that "make it through" the first-line filters, get reviewed to see if they could be SPAM as well. SpamSieve will "learn" over time which are actually SPAM or not, as you will participate in training it.
FWIW, since I have deployed these steps, my SPAM has been reduced by 90-95%
Before I leave, let's go back to your BellSouth account. Since you have been using this, you most likely, have a number of contacts that you use it with. Here are a few suggestions to help you transition off this account:
- For your business contacts, change your BellSouth address with the Microsoft/Google address, so that they start sending messages to those account.
- For your casual contacts, you have two basic choices: 1) Allow them to continue to use your BellSouth address, or 2) Provide them with your Microsoft/Google address. If you go with the former, unless BellSouth offers any type of SPAM filtering, all of those messages will not be filtered ... and, in this case, you can have them forward to your Microsoft/Google address to get that filtering.
Hope this makes sense, and can help you with this situation.