The link above brings you to a presentation of the Button component offered by MUI:
This is very useful if you want to quickly see some different usages & possibilities of the component you're looking at, but if you scroll down the page you'll find a link to the API doc of the component:
Which will bring you here:
Where you can see every property available on the component! For example, we can see that the Button offers a "disabled" property, whose default value is false. Now you know that's something you could use in your app, and how to use it.