laziness

Question
my guinea pig will just sit for hours and is that healthy because he looks fat and i can take him in a purse and he loves it so much that he sleep almost all day in the purse.

Answer
Why are you carrying your pig around in your purse? Unless your purse is very large I can't imagine he has much room to move, so it seems logical that he would sleep.  

If he's getting fat he may not be getting enough exercise.  That's not healthy for him. If you want to take him for an outing maybe some kind of small exercise pen that you could easily take with you to a park or maybe just out in the yard where he has some room to run a bit.  If you do that be sure you don't leave him all alone out there.  He would be easy prey for a hawk or an eagle looking for dinner.  

I should think a shady tree with some grass underneath would be a much better outing for him than being toted around in a purse. And I'm sure you'd attract a few passing 'neighbors' wondering what on earth that little furry thing is.  Might be a great way to meet new people.