Herseas2 Piece Tracksuits for Women Activewear

Looking to buy this for my daughter. She is 5’10 - 165 lbs. would I buy a large or medium? Thank you.

Do i have to purchase the pants with the tops?

how thick is the fabric? Can you wear it in 20-30 degree weather or is it more for the spring and fall?

are the pants tall woman friendly?