Starting sport seriously

I went to run tonight as i'm trying to be more healthy. I'm used to walk a lot but not running ,my body was in pain very fast. But i guess i'll be used to it the more i exercise. I also passed by an art exposition that was saying "free entrance" there was food too but i was anxious to go in as the people inside were well dress and i was in sport clothes and covered in sweat. 

I need to find a sport program to do, some days of the week i'll run and the other i'll do exercises like push up and sht to work more on the muscles...