updating to latest kodi says not enough space

hi i didnt know where to put this subject so im trying here,i have generic hptc box with intell celeron prossecer 1.8 with libreelec with kodi17.5 on but am trying to update to lea18 but when i try to do manual update it comes up error not enough space partitions need resizing i have done hard reset a lot times and tried again,all this i do by usb using libreelec usb creator is there any way to format my hard drive,thanks in aticipation.