Goa has beahces....if u r a beach lover and wanna do some activities goa is good....but in Kerala u can find beaches as well as nature beauty like water falls, forest, u can experience trecking , kayaking , wild life ....
Hey! Both Goa and Kerala have their pros and cons but if you are the party kind, Goa is your place and if you are the relaxing and chill kind then Kerala can be soothing and refreshing with it's beaches, forests, waterfalls and greenery.
Both have its own charm.. goa has water falls (do check out my goa blog),beaches and party places and Kerala has backwaters and beaches but for now i would suggest Kerala if you live Kerala, Goa if you live in Goa.. try to stay in your state if possible :)