How to navigate to another screen according to the text in editText?

I want my app to be such that when the editText1 has value (2) without brackets in it, the button press (with onClick="k") would navigate to MainActivity2. And if the text is (3), the activity MainActivity3 would open. I guess it'll use If function. How can I just implement this in my app? Sorry for silly questions, I'm just a newbie. ;-;