How to drain and flush radiator vw polo 98?

[CharlieFowler]

I am looking to drain the coolant from my vw polo 98 as it has become diluted, i know i need to remove the bottom hose from the radiator, i can see one end of the bottom hose is connected to the radiator which is less visible and the other is connected to what could be the thermostat does it matter which end i remove? also after removing this hose and the top hose, how do i then flush the radiator?

Thank you so much for your help