Like sadness I feel happiness is an experience (emotional/mind based). As you say, we will all experience a vast range of emotions - which result from our life process. We may enhance positive emotional exopreinces and minimise emotional suffering be thinking, deciding and behaving in ways which optimise the likelihood of positive emotional experiences - though we do not control many aspects of like that determine these experiences. Sorry that's a bit long!! The doing is in our decisions and behaviours, the experiences are far from certain and range widely, we are wise to educate and train our minds to be equanimous in the face of these experiences as they are naturally part of life process - whilst working to reduce suffering, for ourself and others, and enhancing the opportunity for enjoyable experiences.

I liked your comment "Happiness is a verb not a noun." I'll keep it in mind as I continue in the lockdown.