When it comes to using TVs as monitor there are certain things you have to do to get the optimal text clarity.
1. Like EndlessWaves mentioned, use the native resolution of 1366x768 for your display.
2. TVs generally have a subpixel layout of BGR as opposed to RGB which can affect text rendering. Windows by default expects a RGB subpixel layout and renders text with that in mind. To change this, type "cleartype" into the windows search, select "Adjust ClearType text", make sure "Turn on ClearType" is checked, "next" and select the box on the right which is BGR - left is for RGB subpixel layout. The following screens will show you a selection of boxes and is your preference to select which ever one improves clarity.
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3. Some TVs can detect PC sources and will use 444 colour otherwise it will use 422 colour with chroma subsampling which does affect text rendering. If the TV defaults to 422 colour then you may have to tell it to use 444 colour. Easiest way is to find a setting in the menu, but TVs will apply 444 if you label the input as PC (Samsung) or Game. For TCL you will have to label the input as "computer" to apply 444 colour.
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Hope it helps