@1aa05329zv6 Please check out these links on how to post in the future: How to ask Great Questions v2.0 + Community Guidelines
Please also look at the tutorials, and checking out other posts before asking another question.
Answer to your question: Go into the Thunkable Live App, click “Sign in with Email”, have it generate the code, then put the code into this box shown in the picture, then you’re all set! If you use the same account on both your phone and the project, then you won’t need to go through this step.