Rice doesn’t work. It’s a myth. You need to stop trying to turn it on and off. This can cause irreparable damage. You need to open the phone and properly dry it out and clean it with isopropyl alcohol. If you are uncomfortable doing this, find a reputable shop to properly dry it out.
You are on the right track, but remember the logic board has to relay the touch info to the processor and the screen is plugged into the logic board. If the board took a big impact and any traces were broken during the impact, then you may be out of luck. I don’t micro solder so I don’t know if there are any fuses etc that can go out or need to be replaced, but your issue is more than likely a board-level issue. Id find someone reputable to send it to.
In all fairness, your device is 10 years old. Are you certain these apps are compatible with your version of Android OS? Newer cheap Android tablets are available for 30 and 40 bucks now. I dont jump to buy new too often, but in this case you’d be better off getting something else.
Definitely replace the battery first. If this does not solve the issue, try a restore to factory. If all else fails, it could be a board-level issue. I have seen this behavior for the Note 4 and 5 as well.
You cant unless you replace the panel which by the looks of the age of the TV would either be impossible to find a part or not worth it. Those lines are on the LCD panel itself. Youre best bet is to buy another TV. Luckily 40 to 43 inch TV’s are very cheap these days.
The glass on many new phones is VERY difficult if not impossible to replace without breaking the display. You would need to invest in expensive equipment such as a glass separating machine, laminating machine, enclave, UV light and various tools and adhesive. In short, you would be saving money by getting it repaired opposed to buying all this equipment.