What is the effect of using pasteurized milk in cheese making?
Unfortunately, the usual store bought pasteurised milk undergoes a process that kills virtually everything needed for coagulation to occur, which basically means making cheese becomes a whole lot harder.

The cheese you buy from stores that is made from pasteurised milk is either made from low heat pasteurisation or by the addition of additional ingredients, typically calcium chloride.

I have no idea where you may be able to acquire calcium chloride where you live but you may be able to obtain low heat pasteurised milk from health food stores, maybe some of the larger supermarkets will stock it, also.