i already used 15% of my inodes which sucks, because i dont know how to free it up and i dont know what it is
Inodes are files and directories on your account. So to reduce your inode usage, you need to remove files and directories!
However, 15% inode usage is nothing to worry about. Most CMS require thousands of files to work, so a plain WordPress installation might already put you at 10% inode usage. As long as you don’t have plans to install dozens of different applications on your account, you have nothing to worry about.
are you sure? it is 61% and i have wordpress and whmcs installed, atleast you stopped me from installing a new whmcs template