You should try the Windows+P key when the monitor and TV are connected and the TV set to the HDMI port from the PC then select Duplicate to start with. You can refine this later.
I thought this was going to be easy. Connect HDMI cable to PC, turn off ‘both’ TV and PC, connect other end of HDMI to TV, turn on TV and ‘then’ PC.
Long story short, desktop icons appear on TV “NOT” on desktop PC. Because of this, can’t set up ‘second’ monitor. The only thing that shows up on my PC is the ‘taskbar’ and the mouse pointer. When “TV” source is set to hdmi, I do get the ‘desktop’ with all the ‘icons’ "ON" the TV. The few things I can click on my “PC”, do show up on my TV but I can’t make ‘changes’. When the hdmi is disconnected from the TV, all my icons return to my desktop PC. If you try and go to display to setup a second monitor, well its ‘not’ listed because you aren’t connected.
Dell desktop PC, running Windows 10, all updates. No other issues with PC. Recently ran my 'anti' stuff, as usual no problems found.
Thanks in advance for any suggestions.

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