Thank you for sharing the data. I have done the following steps.
1. Added (x,y,z) in the first row of the csv. They will act as the headers.
2. From Catalog pane of ArcMap, right-click the CSV file > Create Feature Class > From XY Table.
3. Chose the following coordinate system : "WGS_1984_Web_Mercator_Auxiliary_Sphere".
Saved it as a shapefile.
4. Added the shapefile to ArcMap. Hope this is the correct overlay.
5. Here is where my concern arises. Your data spans across two UTM zones (WGS 1984 UTM 18S and WGS 1984 UTM 19S). In such scenario, UTM is not the appropriate coordinate system to go with. Let me know if you still want to choose a UTM Zone (which one), or work with an alternate coordinate system that is appropriate for the whole area of interest.
Think Location