I think Captain America dies here. Makes the ultimate “American” sacrifice to beat thanos. Other than that it could be iron man since he’s the backbone of the franchise, of Captain Marvel to push the franchise on.
I'm calling Captain Marvel finds Tony adrift And brings him home safely.
I have to watch Antman and Antman and the Wasp in order to possibly understand how they all come back (if they all come back). Rumors say that the concepts in those movies lead to possible explanations. Never had desire to watch them but just got Antman from the library and will get the sequel next.