Yes. The reason they told you write down your negative thoughts is to energetically get them out. It doesn’t mean they will go away permanently (because we cannot stop our thoughts all together) but we can get them out and write it out. Then we burn the paper as a way of “letting go” and detaching from the negative thoughts. You can do this with anything though. If you are having a rough day and just want to vent, you can write about it and then burn the paper. You don’t have burn the paper either, you can rip it up or shred it and throw it out too – same thing and safer.
And if you feel you want to work on your thoughts, CBT (cognitive behavior therapy) can help, meditation can help too. There are many different types of meditation out there. The goal isn’t to stop your thoughts but to gain awareness of them and let them go.