I would like to ask, do I need to buy tickets in advance for the Nantou Bus from Taichung to Cingjing Farm and Sun Moon Lake? Can I buy it on the day?

Generally not required. Every day there are nearly 20 buses to Shuishe in Sun Moon Lake, and nearly 10 buses to Cingjing Farm. You can also take the passenger transfer to Puli to go to Cingjing Farm.

As long as there are no consecutive holidays, the Sun Moon Lake line in Taichung will not be full. You can just buy a ticket on the day. There are few direct buses from Taichung to Cingjing Farm. If it is really full, you can choose to take a bus from Taichung to Puli, and then from Puli If you take the bus to Cingjing, there will be many more trains, so you don’t have to worry about not being able to buy a ticket.