Help with Amp and Projector

Hi everyone. I'm, not tech-savvy so please be kind.I'm now running into major problems with receiving audio. My projector only has a 3.5 mm audio out and 2 HDMI with which 1 is used for the fire stick and my amp/home theatre has optical,1 HDMI out and left/right (red, white)AUX. I have tried these combinations below with no success. Ideally I would like to run the fire stick through the amp, then amp to the projector . Can anyone help educate this old man, please.

Optoma HD143X
Samsung C555 Home Theatre


3.5mm from the projector to left/right in amp
3.5mm to 3.5mm to the amp via the headphone socket
3.5mm to optical to amp

Optical to optical runs fine through a BT Freeview box but I just want to use the firestick plugged into the projector or amp and receive audio. Do I need some extra hardware, or is it even possible? The surround sound amp has red/green/blue/white and red connections. Would this be able to connect the firestick with a HDMI to 1080P Component Video (YPbPr) Scaler Converter and then run the projector through the HDMI out to the projector and carry audio?Any help would be great as I'm at my wit's end. Many thanks in advance Rich.