I rode a contend as my entry level bike for about 2 years before I upgraded to another bike.
This isn't the type of bike you want to upgrade components on. Take that money, save up for while and get a better bike when you're ready and you know more about what you want.
I would say that you should definitely buy better tires because the Giant stock ones are paper thin and suck and you should get a professional fit. Those are game changers.
Te only