If I woke up and cannot = couldn’t use my phone for a day, is ok = it would be okay, but I don't think I can't = could survive without a phone for a week.
Because with = With my phone, I have to text to Ireland and with Hwasong friends. = friends in Ireland and Hwasong.
And I have to check the time.
Also I have to call or text with my parents after school.
Plus I have to check the weather and check my reminders. = I also have to check the time, call or text my parents after school, check the weather, and look at my reminders.
And my life will change a lot. = or Without my phone, my life would change a lot.

Notes:

** could (past/future hypothetical situations use could)

** Use consistent tense: would for hypothetical situations