Step 1.
If you already have a google map based web map, you can duplicate by "Save as" to a new copy, rename it.
for example, click to open it
Step 2.
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setting tab, make sure, allow other user save as
Step 4.
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a new copy is here.
Step 7.
if you want to add google map to a existing web map. you can just add it within web map
Step 8.
to find out what URL to use, click properties in arcgis pro
Step 9.
google map URL is here, click copy button
https://mt1.google.com/vt/lyrs=y&x={col}&y={row}&z={level}
Step 10.
past url here
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