it improves the quality a bit, but as long as the player and the DVD are not 4K capable, you won't get 4K on your TV. I hope I could help you a little bit.
You can connect the player to your computer via HDMI if your computer has an HDMI input to transmit picture and sound. The player has an HDMI output but no HDMI input, so a connection from the player to the computer is only possible if the computer supports HDMI input.
The player also has a USB input, which is intended for USB devices such as memory sticks, but not for connection as a player to the computer.
The device cannot transfer CDs to the computer. It is a Blu-ray and DVD player with USB media playback and upscaling, but no function for ripping or transferring CDs to a computer is specified.
Yes, you can play ordinary CDs with the device. It supports CD audio, CD-R and CD-RW, as confirmed in the official specifications. Greetings back, Jürg!
Yes, you can play CDs. The player supports CD audio, CD-R and CD-RW.
The connection to a soundbar or TV is made via HDMI. The player has an HDMI output, which is used to transmit audio and video signals.
The BlueRay player is connected via an HDMI cable. This assumes that your TV at home also has an HDMI connection. Most Samsung TVs have this - unless they are 10 years old ;)