Importing Points with Latitude and Longitude - anthonyblackham/GIS-Wiki GitHub Wiki
Importing points based on latitude and longitude fields is a pretty common thing. Points will generally come from GPS units or Google Maps. There are a few tools in ArcMap to import X Y Data.
You will want to make sure your spreadsheet is clean (remove duplicates, sort out null values, CamelCase Titles, remove filters etc.)
You can add your data with File >> Add Data >> Add XY Data
Then you can select your spreadsheet (X field should be Longitude, Y field should be Latitude, Z field is elevation)
If there are problems you can try using the Make XY Event Layer
Datum will usually be WGS84
Once your layer is created you'll export the data to a shapefile or feature class.
You'll need to project
it to your coordinate system if your project isn't using the GPS' datum.