Phone touchscreen is broken not sure what to fix.

You will have to replace the screen and the LCD. It up is possible to do it at home, you will have to order the parts online. Good luck.

how much will it cost as in total after buying that replacement screen and service charges?

"Hello Sakshi,

Were you able to resolve your issue. If you fixed it, can you share your experience on where you bought the parts and got it fixed. Am having the same issue...

Thanks,

Suman"

you have to get a micro connector for the phone and then plug a usb mouse into it. you can use a bluetooth mouse to get in. the mouse will work if you have the adaptor. my worked with screen broken. the sensors are not broken, just the haptic (touch sensors) don't work with the broken screen. these one plus models have a more bonded screen than others. sometimes i can turn my upside down and it works. best with mouse connected.