BlackSheep This topic is not for doing any support like that
And the topic magically pops out of your thread!
Basically, Luongmyno, the prevailing solution is to have a local (via XAMPP/WAMP/etc) copy of your flarum installation. Then you can update and install extensions there, and then upload the new files to your shared host with a database backup. It means a lot of shuffling back and forth, the better method is to find a host that offers SSH access, but you can do it if you're pretty dedicated.