Can't see a map or select pokémon
Test to see if google maps works and can get your location.
If it can get your location then perhaps somehow the app does not have permission to access your phone's GPS location? Since you've turned off mock locations and have high accuracy turned on I can't really see any other reason, so perhaps reinstalling the app would help.
If your google maps also can't get your location then it probably means you're simply not getting GPS signal wherever you're and I suggest trying a different place.