There are two ways to install a theme into WordPress. You can use either the administrative interface of the publishing platform or load the theme directly into a specified folder via FTP. Each way has its restrictions because you need sufficient access rights that some free hosts may not provide. Any user should be able to add a theme via FTP, but nonetheless it is necessary to gain access to FTP and use an FTP client to load files.
Using the administration interface is quicker and easier. You can choose from a variety of free default themes. In the Administration Panel, go to Appearance –› Themes and then click on Install Themes in the upper menu. There you can search for themes based on their name, number of columns, colour and other characteristics. This way, you can get the theme that meets your requirements. Then click on Install Now and Activate. If you have already found the right theme and saved it to your computer, you can load it into WordPress. Go to the Administrative Panel: Appearance –› Themes –› Install Themes –› Upload.
The second option is to use FTP. Simply move the saved theme into this folder: /wp-content/themes/ and that’s it! Go to Appearance –› Themes, click on the chosen theme and then on Activate.