How to disable buttons via tags?

I have a disable button code in which it disables other buttons on the press of a numbered int button. How would I can I make it find and disable buttons by tags rather than just dropping and dragging each button a dozen times? Here is my code so far:

public class test : MonoBehaviour
{

public Button b1;
public Button b2;
public Button b3;

public void switchbut(int x)
{
deactivateall();
if (x == 1)
{
((I WANT A FIND AND DISABLE TAG FUNCTION HERE))
b1.interactable = false;
}
else if (x == 2)
{
((I WANT A FIND AND DISABLE TAG FUNCTION HERE))
b2.interactable = false;
}
else
{
((I WANT A FIND AND DISABLE TAG FUNCTION HERE))
b3.interactable = true;
}
}

public void deactivateall()
{
b1.interactable = true;
b2.interactable = true;
b3.interactable = true;

}

Just use GameObject.FindWithTag to find the GameObject.

I’ve seen that but don’t understand how to set it up just under each int number nor will the button class work with the findwithtag function.

Find the button’s GameObject with that method.
Get the Button component from it with GetComponent.