Meet kirby in Downtown/Street area, she will invite you to her barn you can milk her and fill up the tank (harvesting the tank at 100% will reward you with the milky coin) , you can also milk anna and katherine.
113 days ago(+1)
For Amelia you need to hangout with her for a run (you unlock the ability to run with her on Wednesday morning I think through normal progression), after the run you'll be back at home with Amelia in your room. Talk to her and ask her questions, there you will see an option to ask her to join the farm.