To transfer project ownership to another member, first you need to give them access to the project via email. Once the user is invited, you can see an option Make owner under their name.
Once you confirm this operation, you will lose ownership and won't be able to change it without asking the new owner to pass the ownership back.
The new owner will receive an email notification saying that they are the owner of this project now. The project will appear in the My Projects section of the new owner's dashboard.
In your turn, you will have this project in the Shared with me tab of the dashboard. The new owner can now decide whether to keep or remove you from the list of collaborators.