How can i draw a border when the UI button is select like my tablet?

Unity Engine
1

I have just received a external keyboar for my tablet and then i realized that when i sleect an icon with the arrows on my keyboar it forms a border around it
How can i do somehing like this on this new UI system,actually how can i select and deselect an UI button with keyboard,is it possible to do it on unity?
Appreciated.

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2

i tried to found a tutorial,but i found a olde tutorial with GUi system

Just to have an ideia to what do,but new UI system is totalyy diferent.