I try to follow interesting people on twitter and Instagram - this uncovers a lot of book recommendations, which I save in an amazon wishlist.

For technology topics, the Cooper Press email lists are great - https://cooperpress.com/

I also subscribe to the Economist and Nautilus - with Nautilus sometimes the authors are active online (e.g. giving talks). Sometimes it is also interesting to follow citations in books or articles.

For talks, I "bookmark" good things I find by including them in a search engine I built: https://www.findlectures.com/