It sounds like you are in a difficult situation and it must be very daunting to make a decision about whether or not to accept the PhD offer from University 1. It's a good idea to consider all of your options carefully before committing to a course of action. Have you spoken directly with your potential supervisors about your concerns about the project? It might be useful to have a conversation to get more information about their expectations for the project and the potential for success. You could also look into the resources available at University 1 that could help you to develop your experience and skills relevant to the project.

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