Hi, can someone tell me how can upload pictures in ArcGis Online maps?
it all depends on where your photos are stored, the following blog shows you how to add photos from Flickr:
Using Flickr photos in the hosted map tour story map | ArcGIS Blog
Using Facebook photos in the hosted map tour story map | ArcGIS Blog
from a csv:
Using the Storytelling Playlist template | ArcGIS Blog
Using Dropbox files in ArcGIS Online web maps | ArcGIS Blog
storing files in arcgis online:
Using photos stored in ArcGIS Online | ArcGIS Blog
Adding geotagged photos to your web map | ArcGIS Blog
Retrieving data ...