Welcome!
First find the right room, not square and not small. Ideally well insulated. Layout should accommodate loudspeakers and listener being located away from walls. Next find loudspeakers that "fit" the room. Suggest active monitors, prices for good ones start around $300/pair (JBL 305 Mk2 or Kali LP-6) and go up from there to incorporate room correction DSP and DAC's. In these modern times streaming is a logical choice for sourcing.