And is there a service out there (paid, free, anything) that lets me build a list technologies like those mentioned above that will keep track of it all for me and notify me when there’s a change I need to know about?
You follow the official news/website/github/releases/twitter/facebook, subscribe to newsletters and other mailing lists.
Facebook is the most powerful tool when configured smartly. Like all the pages, set up notifications, follow events, join local groups/meetups, follow top engineers/authors on Twitter.
I know about any updates in a 0-2 days using Facebook/Twitter and immediately via mailing lists.
For security in general around the globe you should subscribe to the US CERT
For Laravel there is https://laraver.xyz/
Subscribe to US CERT
Use Linux and just update software (c) Always your Captain Obvious
P.S. When I log in to Ubuntu through Terminal I always see X packages or kernel can be upgraded.
Gemnasium may resolve some of your problems.