Follow the steps below to install the theme via FTP:
Step 1 – Log into your hosting space via an FTP software.
Step 2 – Unzip the “[themename].zip” file and ONLY use the extracted “[themename]” theme folder.
Step 3 – Upload the extracted “[themename]” theme folder into “wp-content” –> “themes” folder.
Step 4 – Activate the newly installed theme. Go to Appearance > Themes and activate it.