How can change my attitude to an uninteresting subject?

That comes from within... and consider, you have much to learn from things you might find no interest in.

You have to face up to the fact you will have to do many thngs in your life you may not be interested in, or even outright HATE to do... but a smart person, and might I add a successful one, will take each task they must do, and do them all to the best of their ability.

You have to start someplace, let it be with this. You will be doing it the rest of your life.