How to overcome fear over dogs?

Hi, I’m from India right now I’m in Minnesota, USA. I am scared of dogs I like them if they are 50 feet away with harness.When I was 8 years old in our neighborhood there was a dog closer to the park who use to bark at every one who crosses their home. It had chased me numerous times once I sat in tree for long time because of that dog. I never told my parents I thought they won’t allow me to the park maybe because of that still I’m scared of dogs now it’s summer I like to walk in the park when ever I see a dog in the park my heart beats so fast until the dog crosses I’ll constantly check whether it’s coming behind me. Can someone suggest how to overcome this fear?