How to fix ghost touch in my phone

Ghost touch happens when the delicate connections between the glass the digitizer circuits are printed on and the flex cable going to the motherboard are disrupted, allowing electrical noise onto the signal lines. The phone picks up that noise and tries to interpret it as touch inputs, resulting in random touches all over the screen.

Unfortunately, since the digitizer, or touch screen, is fused to the LCD display you'll need to replace the complete screen assembly in order to fix the problem. Sorry to say, iFixit doesn't have a guide to that repair for your phone, but the Spanish site Nadie Me Llama Gallina has just what you need. As you may guess, it's written in Spanish, but if you use a browser that does translation like the Google Chrome browser, the guide is quite usable and I've found them to be very well written.

Manuals / Xiaomi Redmi 10C / Full Screen - Nobody Calls Me Chicken

A simple internet search will turn up several sources where you can buy a replacement screen; the three most popular ones include Amazon, eBay and AliExpress.