confused and don't know what to do

And don’t spend big bucks on cables first time out. Get the cheapest you can find, then swap them out for better ones, one at a time, until you find something that is worth the cost. I use quality microphone cable (Canare StarQuad) with quality connectors (ETI, KLEI, Switchcraft), nothing too exotic, for interconnect, and continue to find better uses of money than cables - better electronics, better crossover components, better records. Maybe when I hit seven figures ...

I'm not an engineer who can provide reasons why one type of amplifier is better than another etc., but I can provide my experience with wanting a system that can both play music and be really good at home theater. I realize that brands like Marantz, Denon, and Yamaha are scorned by the music listening only crowd, but to me, there's no better or cheaper way to set up home theater than with one of their AV Receivers and then deal with the music listening part of the system with a separate amp. Just be sure the AV Receiver has enough power to drive the center and surround speakers. As far as the AV Receiver manufacturers go, be aware that after a merger with Denon, both Marantz and Denon were subsequently purchased by Sound United. I'm always concerned after mergers and acquisitions like these that cheaper components will be used by the new parent company to increase profits. If I were going to buy an AV Receiver, I'd look no further than Yamaha. They have not gone through mergers, they use high quality components, and have the best reliability ratings of any AV Receiver manufacturer. I'd go for at least a 7 channel amp like this one with a lot of bells and whistles, which would cost a great deal more to get in separates:  https://usa.yamaha.com/products/audio_visual/av_receivers_amps/rx-a1080_u/index.html 
For just music listening, I own a pair of Magnepan 20.1s and I drive them with a separate 300 watt at 4 ohms Emotiva two channel amp. I also use the Maggies as the front speakers in the home theater setup. To my ears, the system works great for both music listening and home theater.

Many opinions found here, can be rather daunting.

Here's my two cents.  Figure (really think about it) out which "system" you are going to use.  If you are a major music fan then build a stereo.
If you watch movies constantly then build a HT.

I've had both in one room.  Totally separate systems.   

Try to remember that music appreciation is a "warm" endeavor, whereas
video is a "cool" endeavor.  

Personally I would build the stereo first, simply because that's where your dollars are going to make a difference.  Home theaters are a lot of fun but not as much as fine music system.  Good Luck.    

The B&Ws are bright - I literally can't listen to them! 
Paradigm has made affordable audiophile class speakers for decades.
They also have a complete line of really good in-ceiling, in-wall and subwoofers. I would check out the Prestige series.
They also make one of the few really good AV receivers - the Anthem MRX 520, 720, 1120. I recently listened to an MRX 720 driving a Wilson Audio left and right, with Paradigm center, surrounds, and subwoofer. With an Ayre DAC feeding it the sound was stunning!

Lots of good advise above but I want to add more thoughts about the room.

Walk around your room and do a single hand clap at various places. Then go into other rooms, especially bedrooms, and do the same thing. In your main room you will likely hear a strong flutter echo. If your bedroom is carpeted and you have a couple chairs plus the bed you will hear a smoother fade-out of the sound. Flutter echo = bad sound. You want your large room to sound more like your bedroom. There is no amount of money you can spend on gear that will overcome the bad effects of flutter echo. One of the main things to know about room acoustics is that the digital correction technology in an AV receiver will do nothing to address flutter echo. It only concerns itself with frequency response, particularly in the bass region.

The next thing is to talk to your significant other about how you will be playing the system. There will certainly be times that you are sitting in the sweet spot listening intently to a piece of music. However, it sounds like this is your main living space which portends other requirements. Do you or your SO like to listen to music when you are in the kitchen cooking? How about watching TV. The point here is that you will need to think about how the system will sound in other parts of the room. If the room is large with a lot of reflective surfaces it might sound like a cave. In this case I would recommend that you think about remote speakers and where they should go. This will affect your choice of gear.

Before researching the optimum system I recommend that you focus your energy and dollars on treating the room. There is lots of good instructional information on the web and there are several companies who provide room treatment products that will have an expert personally assist you to improve the acoustics of your space. There are even custom absorbers available that can be covered by your own artwork or photos.

Lastly I agree with the above posters who recommend starting with a good quality two channel (or 2.1) system. You might find, as I did, that having more than two channels doesn't improve my movie watching experience. I finally came to the conclusion that the extra speakers were more of a distraction. For movies where multichannel sound is very important we usually go to the theater. We just saw The Rise of Skywalker and it was amazing. I'm simply never going to have a surround system that is anywhere near that good.