Sewing easy curtains for big windows - help please

Maybe someone here can help me out? I have some huge windows facing south AND they are high up. They have no curtains or anything right now. In summer, the sun really blasts into the house. So I would like to sew some curtains that I can easily open and close as needed.

First, what kind of material should I get and where (if it is some specialty material). I don't need to block the sun entirely, but some shading would certainly help.

Second, any ideas about how to open and close them standing on the floor? Some pulley contraption? It should not look too bad, it is in a very public area of the house.

I have never done anything like this, i.e. curtains, but I am sure I can find instructions.

I would be so grateful for any ideas you could share, thanks, C.