The two people who head up Project 2025 are former Trump staffers. Because Project 2025 is divisive, Trump has publicly disavowed knowing anything about it (in the same social media post where he also said he disagreed in large part of it, despite not know anything about it and also wished them well). But much of the things that it talks about are talking points used by the Trump backers, Trump aligned politicians, Trump supporting media and Trump himself (particularly the deportations/secure border stuff). So I find it hard to think that Trump wouldn't try to implement much of this if given a chance.