Welcome!
I always recommend Floyd Toole's "Sound Reproduction" 3rd edition as the consummate audiophile guide to how speakers/subwoofers behave in-room. Toole is an acoustician who worked for the National (Canadian) Research Council for decades before retiring out of Harmon International. Worthwhile review sites include Audio Xpress, audiosciencereview.com, erinsaudiocorner.com, and the Hans Beekhuyzen Channel as they don't take advertising money and actually measure gear.
After decades I've learned to buy from "good" companies (those with deep R&D and manufacturing resources, and relatively long histories). That'll limit your search substantially. For speakers look towards Dynaudio, Focal, and JBL. For electronics start looking at Benchmark or NAD. There are hundreds of would be experts out there selling their gear or promoting how much they "know" who are little more than hobbyists. Note that Dynaudio, Focal, and JBL all offer active loudspeakers, which have several superior technologies.
The priorities for good sound reproduction at home starts with the performance and the recording. In classical music there are numerous versions of the same piece, but for the rest it gets harder. Next is the speaker. Believe it or not technology exist to predict loudspeaker performance, but it's complex and expensive so most reviewers don't use it. The other predictor for loudspeaker performance is the use of a panel of trained listeners using double blind techniques, which many audiophiles pooh-pooh! Finally the room itself is an important factor (size, shape, insulation, and treatment are all factors). This is where most audiophiles fall far short as they get gear fixated.
