“What are a few examples of kusala kamma(actions that purify the mind)?”
They are opposites of the ten akusala kamma.
Instead of killing/hurting living beings, one needs to realize that they also like to live.
Instead of stealing from others, one should give to those in need.
Instead of engaging in sexual misconduct, one needs to live morally.
I provided a post on how to engage in “correct speech” earlier.
The most important is to avoid the three akusala done with the mind: control excess greed, anger, and most of all, to remove wrong views.
“Wrong Views (Miccā Ditthi) – A Simpler Analysis”
Also, see, “Sīla, Samādhi, Pannā to Pannā, Sīla, Samādhi“