[Lina]

How often you have to take out your dog depends primarily on its age.
At the first months you'd better have a place where he could pee inside the house because they indeed need to go out every 1-2 hours even at night ..and just can't "hold it"

My yorkie is now 10months old and i take him out 4 times a day.
Morning: Right when he wakes up, feed him and take him out.
Midday: Feed him and take him out.
Afternoon: Feed him and take him out.
Night: Feed him and take him out right before he sleeps (when its time to go to bed)

In my opinion you shouldn't have food out all day. And only leave water out if the day is too warm or too cold, if it's not your dog will not really need it.
Oh and, something you should know. A dog is more likely to pee when he wakes up, after playing, after bath, and after eating/drinking water. So, be careful.