"basic/free version of wordpress"
By this I am guessing you are working on wordpress.com not using the actual full version of wordpress that can be found here on wordpress.org
And in that case you can't use this theme. Wordpress.org and wordpress.com are different and if you want to use the wordpress found here on wordpress.org where you can have all the themes available on wordpress.org you have to have your own hosting.
Kadence Themes