Give Google all your data. Well you have already given it because you used their services. So give it again and they will tell you when it shows up on 3rd party sites and you can request that info not show up in Google’s search results. Note that the info would still be on the 3rd party site.
I use first@firstlast.tld I bought my firstlast.tld several years ago. Figure it would look good. I then put a modified resume on my domain but when I started to think about being a security professional that didn’t seem like a good idea. I now have my domain bring up the IP, browser, and few other pieces of info and show it to whoever goes to the site. It is either that or blank page and I think the first is more fun.
I have multiple emails. My email for everything which is pretty generic Gmail (I’m slowly moving away from that to a less generic domain) and first@firstlast.tld which is only for business, so I use it for LinkedIn, resume, professional stuff only. Use a place like Tuta and get their app that way you get a notification when you’re business address gets emails. I have Gmail, Tuta, Proton, and Yahoo apps on my phone. All with different email addresses so notification give me an idea of what it is (like Yahoo is probably spam. Gmail is general life stuff.)