I created an experience with experience builder. On the map it has the function button ADD DAT.
When you open the menu it lists it accepts shape files.
However when you try to load on, it appears the format is not accepted?
When i upload a shapefile it says format not supported?
Keep in mind that the Shapefile format is not actually a single file. It is a collection of at least three files. See the Shapefile description here. https://desktop.arcgis.com/en/arcmap/latest/manage-data/shapefiles/shapefile-file-extensions.htm
Also, I believe that the constituent files in a the Shapefile will need to be bundled into a .zip folder for the upload process.
I would recommend converting the shapefile into a feature class and publishing as a feature class, whether that be via ArcGIS Pro or publish directly to ArcGIS Online/Enterprise this will ensure you are not missing any of the files listed in the link (posted by Jeffrey Thompson)
If you are using shapefiles ensure that they are zipped this will make it easier for the upload process.