这个汉字怎么说？ correct! 这个字怎么说？ correct! 这字怎么说？ correct! if you want to emphasize on the pronunciation of the word you can say: 这个汉字怎么读？ or 怎么读这个汉字？ 这个字怎么读？ or 怎么读这个字？ 这字怎么读？ or 怎么读这字？

我怎么说这个汉字？（wo zen me shuo zhe ge han zi ?）这个汉字怎么说？(zhe ge han zi zen me shuo ?) when you say 怎么means how ,and 说means speak,and 这个means this,and 汉字means chinese character.people will know what you want to ask if you mention these words.A little word order error does not affect the meaning of the sentence.(if you are a beginner ,it doesn't matter if you have some mistake ,but i think we should say it in correct way from beginning.:)) and I think the important thing is that you stress location in pronunciation. if you want know 'how'stress‘怎么’ if you want know 'this 'stress'这个' ...... ditto...... i hope this answer can help you.

correct！

這個字怎麼念?

这个字怎么读？zhè gè zì zěn mē dú?