Do I need to show my hotel reservation form when I enter Singapore?

In general, there is no need to show anything. Passport and visa are enough to get through.

However, in the event of an abnormal situation, Singapore customs officers will call you to a small room for questioning, and at this time you have to show anything that is required. Not only hotel reservations, but even cash, credit cards, return air tickets ... you have to show everything you want. However, I have never encountered such an abnormal situation once. Generally speaking, I think you are suspicious before questioning.

If you have any questions, ask them.