date and wifi and battery

hi there

i have iphone 5c 32gb white

wifi keeps connecting and disconnecting , so i can't use internet over wifi

battery indicator is not accurate after i restart the indicators goes from 50 to 80 percent

clock and date always stay behind on automatic and manual

and also i noticed if it is 10 30 after some minutes it goes back to 10 15 like if it is in a cycle

i don't know if this is a software issue or hardware and if it is hardware id appreciated if you tell me exactly what to change

hmzawati@gmail.com