Class140

Hello all! Im new here. I turned my key and nothing happened.
I did it again and it started like new. This happened like twice.
Im scared my starter is going. Can someone or two or three tell me how hard it is to change the starter, where it is, and if a remanufactured starter is out of the question or not. Thank you very much in advance! Hope to hear from someone soon. Enjoy your night!~