<human>: Can you condense the text into three sentences or less?

I'm a 21 year old male about to enter my senior year of college. I think I'm (generally) a pretty smart person but for as long as I can remember, I've never been much of a "study-er" and I probably do just about the minimum to get by for just about everything. The thing is, it's never failed me so I've had trouble motivating myself to achieve more. For example, I recently finished up an internship and received a job offer for when I graduate. It's a big company and I'd be paid pretty well. Thing is, I spent a lot of time during the internship browsing the internet and generally screwing around instead of asking managers for more work or attempting to learn more about the industry or whatever. 

This isn't just a school/work thing. It's affected my social life, my physical appearance (I've been to the gym to work out once in my life), and even my health.

So reddit, what keeps you motivated on a daily basis? Have any of you felt similarly at some point in your life?  I'm really trying to work on this because I don't want to die at 50, alone, with a mediocre job because I never felt the need to go out for a big promotion. I've started doing push ups each morning and evening and I want to keep this up. Hopefully it'll be the first step to a better me.
<bot>: I'm an unmotivated 21 year old who would like to break his old habits and get motivated by life. I need advice.