Want to plug in Yamaha receiver to LG4k TV ?

Solution
What models are your Yamaha receiver and LG4k TV?

How many speakers? Any other devices; e.g., DVD player involved?

Based on the specifications and images that I found by googling you may have a variety of options.

Start with the applicable User Guides/Manuals for your devices.

And these two links may be helpful:


http://www.diyaudioandvideo.com/TV/WiringDiagram/

http://www.ceaconnectionsguide.com/


Just sketch out your own diagram and start fitting things together.
What models are your Yamaha receiver and LG4k TV?

How many speakers? Any other devices; e.g., DVD player involved?

Based on the specifications and images that I found by googling you may have a variety of options.

Start with the applicable User Guides/Manuals for your devices.

And these two links may be helpful:


http://www.diyaudioandvideo.com/TV/WiringDiagram/

http://www.ceaconnectionsguide.com/


Just sketch out your own diagram and start fitting things together.
 
Solution
You can connect all your sources to the TV with HDMI and use the TV optical digital audio out to connect to the receiver. Check that the TV will output in surround sound, turn the optical on, and the TV speakers off.
If the receiver has HMDI inputs you connect all your source to the it and run the HDMI out of the receiver to the TV. If the TV and the receiver both have ARC then you would turn it on in the TV. That would get sound from the TV tuner and smart apps to the receiver through the one HDMI cable. The alternative is to use an optical cable from the TV to the receiver for those sources.