Sinotec led tv blinks then adopts whitish screen

Question edited for clarity.

There is a rather 'round about' way of doing it and it starts with your computer!

Installing Apps using APK Installer on my Sinotec TV Home screen

• Open your browser on your computer, find the APK file you want to download, and select it.
• Once the App is downloaded, open Downloads, right-click on the APK file, then save to USB or external storage device.
• To install this APK from your storage device to the TV, plug the USB into the TV.
• On your HOME screen, go to APK installer, and select the APP you would like to install
• The app will begin installing on your device.
• After the application has successfully been installed the user can run the app with no issues.
• Please Note: Only selected smart models have the "Install APK" function.

https://www.sinotec.co.za/support/faqs/

Specs for your television says it comes with

• Netflix
• YouTube
• Twitter
• Facebook
• Mirashare
• Digital Dvb-T2
• Child Lock

Sinotec 58" UHD Android TV

Sinotec https://www.sinotec.co.za > product > sinotec-58-uhd-...
Open Browser: Yes; Prime Video: Yes; Netflix: Yes; DSTV Now: Yes; Showmax: Yes ... STL-58G50UM. Sinotec 58? UHD NETFLIX LED TV. Resolution: 3840 x 2160. View ...

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The backlight led is burnt out, time to replace with new one. Most of the time it’s only 1-2 led are burnt. You need an electronic technician though. I may guide you if you want further assistance.

Sinotec STL-55N86UM 55" UHD Smart LED TV
that, is not PC it is TV.
there are only 2 cures for TV
upgrade its screen APPs on the TV, from makers web site
or buy , many TV fail now. old. many are hopeless in there own right.
but.....


Roku box and use that that updates, automatically.

https://www.roku.com/

That looks like tcon board failure however finding a board me not be easy

The set has an internal fault and needs to be serviced