need advice getting started with 3D web maps

[L77]

I created a 2D Experience Builder web map of our landfill using orthophotos, hillshade, colorized surfaces, and contours.

Example photo:

My boss asked me if I could make one that is 3D like google earth, with the ability to tilt and fly over.

I am looking for advice on what to do.

I have already published my data  in AGOL as tile layers from Arc Pro but they were 2D files. 

Should I use these files in Scene Viewer, or should I convert the files to 3D files in Arc Pro them publish them again online and put those files in Scene Viewer?

Is Scene Viewer the best place to make a 3D web map. I saw that Experience Builder has a few 3D tools so what is your preference?

As I side note I tried adding these tools from experience builder but they all said "please select a map that contains 3D data":

What will give me the best results?

Thank you.

[L77]

I just want to update this thread in case this helps anyone else later on.

I was able to load my hillshade, contours and drone imagery into scene viewer but the tool was not useful for the data we want to display in 3D.

The reason being that we have different models of our landfill, preconstructions, current state, and final state with different elevations and contours. 

After loading all of the data into the app, all of the data was draped over the current topography so the final contours which are much higher in elevation were simply draped over the much lower elevation current contours of the basemap.

I ended up deleting the app and will not be working in 3D. It is better visualized in Experience builder in 2D.