Website app issue

Hello. First of all I would like to thank you in advance for your help , and please have patience with me as I am a complete beginner with android studio. If you answer to my problem , please answer considering that I am a moron . My problem is that with the help of YouTube videos o managed to make an Android app of my website , everything works fine , just it does not refresh , and the biggest problem is that if my users are trying to add a photo to adding a listing the pop-up of photos to choose the photo you want for the listing does not appear. The button is changing color when pressed but nothing happens. Please , a quick reminder that o am a complete beginner and probably a moron who needs step by step information. Thank you very much.
https://play.google.com/store/apps/details?id=com.emagsh

 

Thank you very much