I logged in with my user account which has project ‘My User Project’, but when i open Cloud Shell terminal, it wont show the project. Instead it shows (playground-s-11-8265d154)
Cloud Shell only displays project ID in shell prompt, so what you saw was the ID of your “My User Project” project.
Project name and project ID don’t have to be similar. However, you can also select the project you want by typing "gcloud config set project [PROJECT ID]"