Toddler and newborn outing

I had a baby two months ago and my first child is three years ago. I am unsure how to take them out by myself to parks and outings. Can i let the baby nap in the stroller when i let the toddler play in the park. Would it be safe to be a few feet away engaging the toddler when baby sleeps. Toddler is potty trained so what to do when he wants to use the restroom when we are out with the baby. I am freaking out on how to handle these situations. Mom’s of more than one kid, how do u handle these situations?