I get raw milk and to somehow pasteurize it, I boil it. The milk strongly curdled showing that it is spoiled and rotten (definitely, not suitable for drinking). Is it totally bad milk and I should throw it away? or it still can be used for making yogurt and cheese?
Even if it is possible, it is a very, very bad idea as you don't know what cultures or pathogens are in the already spoiled milk.
Fermented dairy products should only be made from fresh milk in good condition—and in most cases, that milk should be pasteurized while fresh absolutely as soon as possible from the source cows.