Change

It’s been so long time (or 'such a long time') that I haven’t since I've written an English notebook entry. (I changed your sentence, but it's clearer this way) In fact, I have been thinking of writing something all the this time, but I don’t know what I should write, because my life is so quiet and simple. Everyday Every day seems so similarly similar, nothing quite different (or 'not all that different') from the previous day.
I think I should do something to change this status ('status' is a little too analytical in this context). I plan to change to a new job next year. For the interview with the  new company, I need to practice English more in the following days (following from where? do you mean 'I need to practice English in the next few days'?) till I find a new job. (Make sure that a sentence deals with one idea only. I'm not sure if you're practicing English for the interview or if you're practicing English till you find your new job)
In daily life I often sit in front of a/the/my computer to work, view pages (do you mean 'web pages' or 'websites'?), and watch movies. I am very lacking of in exercises exercise. It’s harmful to my health. So Yet I want to do some exercises exercise; jogging is a good choice. Jogging is easy, but to keep on doing it is difficult since I am so lazy and I lack of constancy of a constant purpose ('a constancy of purpose' is okay, but less common). I hope I can do it 4-5 times weekly. If it rains, it’s not suitable for jogging outside, yet I can climb stairs instead.
If I make a little change (or 'little changes') for a every day, one day I will find I have made great changes.