I bought this one on Amazon. It's actually a little bit more than it was a few weeks ago when I made my purchase. It still has a $50 off coupon right now. I use a fire stick to stream YouTube TV, ESPN, etc.
[1000 ANSI & Audio by dbx-tv] Alvar 4K Projector with WiFi and Bluetooth, NetfIix Certified & DoIby Audio, Auto Focus and Auto Keystone Native 1080P Smart Projector with HDR10+, 30W Speakers, Black
https://a.co/d/dri3wIm
For my screen I just upgraded to the 150" one.
I mounted it the side of my house next to my patio. You can get screens that have self supporting stands.
AAJK Outdoor Projection Screen 150 inch, Washable Projector Screen 16:9 Foldable Anti-Crease Portable Projector Movies Screen for Home Theater Outdoor
https://www.amazon.com/dp/B08Z35TJRJ/ref=cm_sw_r_apanp_FcPt4Na7iirHG
As to Audio. The Projector has a built-in speaker but it's really not adequate. I have a Bluetooth speaker that I use. The Projector has Bluetooth but I've had issues getting it to connect so I just use an aux cable. I really want to improve my setup somehow to incorporate surround sound.