My D said the single most helpful HS class for engineering was AP Physics C, both mechanics and E&M.
My D is a chem E and only got through AP Calc because that was the highest level math offered at her school. Worked out fine for her. In college she took Calc II and Calc III, linear algebra, diff eq, and a Calc based statistical modeling and probability class. There is a ton of applied math in all of her chem e courses but that was it for straight math courses.
In term of other STEM courses in HS, she took AP Chem , AP stats, Organic chem, CS, and then her school’s project based engineering courses. No room for AP biology but she did have a year of honors as a freshman.