The biggest difference between the two is that the so-called admission is admission, just admission. The school won't give you any money, so you have to bear all the expenses. What about the offer? On the basis of admission, you get a scholarship provided by the department. In fact, it is not a scholarship in the strict sense, but a kind of assistance, and the number is often large.

AD: There is no scholarship or partial bonus or credit reduction at all.

Proposal: Admission+Full Scholarship (tuition remission/monthly allowance/in-state tuition)

The forms of scholarships: first, non-service scholarships, including scholarships, grants, tuition allowances, etc. Another service scholarship is returned through labor. Scholarships for teaching assistants and research assistants are obtained by helping teachers do research and being teachers' assistants. This form is more common for graduate students.