The most confusing facet of putting is green speed, which is indicated on top right and changes a lot while in the first tiers.
Other than that, it's "simple". Some hints:
- all balls act the same on the putting green, putters differ.
- putting power is linear. A 5% putt goes 5% of the full length.
- meter speed rises with amplitude - chose a higher scale.
- grid colours indicate elevation, moving dots indicate slope.
- treat any "-0" indication as uphill ;)
There are putter movements to help judge the pace, and Putter Pal for a power grid. There are some tables for the different green speeds available, and other advice => search.