I remember when the main way to answer that question was to watch the News at Ten. More sophisticated people would read newspapers. The limitations of mainstream media are ever more apparent. The internet democratized information, so that should help. There are still various problems, including filtering and resources.
YouTube is probably the most successful solution to the latter problem. It is possible to be a full time YouTuber focusing on a niche topic and earn a living.
The former problem is hard. Search engines have bias; bots abound. I offer here a handful of ways I figure out what is happening.
To answer specifically what is happening, lately I have found the Miltary and History channel useful. In the linked video he explains what is known about the results of the US strike on Iranian nuclear facilities, complete with satellite imagery. He has daily updates with information about multiple conflicts with lots of detail. He is analytical and unpolitical.
To answer why it is happening, William Spaniel’s channel looks at events from the perspective of crisis bargaining theory: it is war economics where territory is the currency, hence the refrain that everything is about “lines on maps”. In the linked video he explains why the USA bombed Iranian nuclear facilities when it did, in terms of Israel setting the stage and creating a window of opportunity. More generally, the channel is useful for understanding why fighting is happening instead of negotiating, and how different things will have to look before negotiation is possible.
For a broader perspective of capabilities and defense economics, there is Perun. He explains the principles, brings in real world data and describes the range of possibilities. An unexpected bit of information in the linked video is that Israel would likely run out of ammunition for its iron dome before Iran runs out of cheap, badly aimed ballistic missiles. That is why eliminating launchers is so important to Israel, and it affects how long an air campaign can go on for.
In general, if I really want to understand something, I have found that finding a good specialist YouTuber is one of the better ways to do it. The feedback loop of financial reward and algorithmic feedback seems to work: not universally, but enough that there is a rich vein of good information on any given topic amongst the noise.
For something lighter, I can also recommend Daniel Owen if you are looking to buy a GPU for your computer, and Chris Spargo for dull yet fascinating pop history like the story of nationalised pubs.
Please add your recommendations in the comments.