[HP] Gloomy Harry

I recently re-watched the Sorcerer's Stone movie and wanted to write a HP fanfic. I don't think Harry can still remain happy and courageous to enter Gryffindor after 11 years of oppression. I also want to solve the problem in advance and bring peace, so let this Harry be time-traveled. The protagonist knows the plot and will work hard to solve it. Maybe watch some British and American dramas. Intention: If the problem is solved, can fate give everyone the best ending?