Yes, you can play five nights at Freddy on a computer. The steps you need to take in order to do so are as follows:
1. Go to the website for five nights at Freddy.
2. Click on the link that says "Download."
3. Follow the instructions that come up on your screen.
4. Once the game is downloaded, double-click on the icon to open it up.
5. Follow the prompts within the game to begin playing.