This chapter of the guide to Dragon Ball Z: Kakarot has a walkthrough for Perpetually Attacked Villager side quest.
Time frame: From Majin Buu Reborn - Episode 8: Finale to No time limit
Reward: 249,984 EXP, Cooking Medal, Fancy Wristwatch
Where to start: Southeast Mountains Area, as Gohan.
To start this mission, you need to go to Yamcha's Hideout. There you will find the attacked villager.
Your task is to kill the monsters attacking her. The enemies shouldn't be a threat.