In early 2018 I bought a smart tv ( Mi LED TV 4A ) for my parents. I see no third party apps installed on it. My parents told me the TV had issues a years back and guys who fixed told them the motherboard was changed since it wasn't able to boot-up. I wanted to try out some OTT apps but since it has no play store I am just not able to install any apps. I tried installing via USB, apps get installed but either crash or don't work.

The only apps that seem to work on it, gets installed automatically without any hassle is what's comes in its feed. Like amazon videos comes in its feed and if you click on it, Amazon Video gets installed automatically and works fine. But how do I install other apps I want like YouTube on it?

• It does not have app store. I tried installing play store via USB. It installed but when opening it goes to sing-in page and gets stuck there. I am now guessing other play store services are also missing?
• I tried using aptoide also, again it works and I am able browse apps but it doesn't allow me to install any app since I am not able to move cursor to "install". Its just not working as if either the app or tv input is not compatible.
• I also tried installing YouTube for Andoird TV directly again with USB - It gets installed but doesn't even open up.
• Tried YouTube vanced manager also. It gets installed, but I am not at all able to move beyond its welcome page. Again, it seems inputs are not understood or they are just not compatible.

What am I missing here?