"What is a day today?" and "What day is it today?" essentially mean the same thing. Both questions are asking for the current date or day of the week. The only minor difference is in the phrasing of the question.
"What is a day today?" and "What day is it today?" essentially mean the same thing. Both questions are asking for the current date or day of the week. The only minor difference is in the phrasing of the question.