command line - How can I open (launch) files using the terminal?

Objective: Open a text file and other types using the terminal.

Let's suppose I have a file named myFile.txt and I want to launch this file (open it, not sure how I'm supposed to say it), how can I do this?

As I searched all I could find was articles about create and edit files or display the content in the terminal.

Some of the failed attempts:

./myFile.txt

/myFile.txt

cd myFile.txt

cd ./myFile.txt

cd /myFile.txt

eog myFile.txt

And, yes, I used the commands in the folder containing the file in question.