must you have this at the end of my joomla site ? Basically take it off does it violate any terms ?

Joomla is licensed under GPL version 5 or later. You're liberated to take away the link in the template, or make your own template without the hyperlink. When you are needed to depart the copyright and license notices within the code, you aren't obligated to depart the hyperlink to in your public facing website.

this is a link of methods to get it done.... I am unable to recommend the legal side from it.

Consult the EULA

You may also by hand edit the index.php file situated within the template folder, for example mydomain/www/templates/yourtemplatename/index.php,

You may also take away the link inside your en-GB.mod_footer.ini (~/www/yourdomain/language/en-GB). It's most likely the simplest method of doing it.