Well, it depends, as beginner, many piano teachers would recommend you to buy an electronic keyboard, then you can practice everyday to build your foundation, and it won’t be too expensive.
If you just want to learn how to play a easy song on piano, you may want to find a piano teacher who will give you a few sneaky lessons and focus on teaching you just that song that you want to learn. That case you can probably learn piano without owning one although it’s not ideal.
If you want to learn piano without owning a piano, you can try the following:
- Find a friend who may have a piano at home
- Hire a piano teacher who are willing to let you practice for a few hours each week his studio with a piano
- Some churches may have a piano that you may be able to spend some time with
- Take piano classes at a local college that will give you access to a piano
- Some other places to try including your local library and the University