PossibleCabbage |
The obvious religion choices for a druid are Gozreh (nature god) or the Green Faith (literal nature worship) but both of those are True Neutral (you can still worship them as an NG character, however, you don't need to match the alignment of your deity, within one alignment step is the generally accepted standard.)
If those are out, the question then is "why would a Druid worship something other than nature/the nature god". For a good aligned deity for a druid to follow, I'd personally recommend Desna (so be NG). In part because Druid PCs tend to be the kind of Druid that travel a lot (as opposed to those non-PC Druids who guard the sacred tree forever), and Desna is the goddess of travel and travelers. A reason a Druid might worship Desna (apart from a fondness for butterflies and stargazing) is their desire to help their Goddess retake the Beasts domain from Lamashtu (the monster goddess) who stole it when she killed Curchanus, who was Desna's mentor