Sentinel5p is not explicitly supported by SNAP, it can only read the NetCDF in a generic way.
But you can use BEAT. Have a look here:
https://sentinel.esa.int/web/sentinel/user-guides/sentinel-5p-tropomi/software-tools
The download of Panoply can easily be found by a web search.
Here you are: https://www.giss.nasa.gov/tools/panoply/