How do I get a component of canvas?

Hi people, I wanted to know how to use the function getComponent or another to take a variable from one canvas text, from another object and modify it from it.

Example: When the script of a gold coin to activate this add 200 points to a variable that has a canvas text

Try to do it but always get an error, I wanted to know the best way to do this with the new UI, In itself, it would create a scoring system with the new UI.

Thank you in advance, sorry for the bad English.