My forum in hacked what should I do?
If you're referring to your 000webhost forum, there's not much you can do but to contact the host for help.
The free hosts provide you with very limited control, I sure hope they have backups.
Initially I change my username into the picture
Then I logged in and can not
there is still hosting my password
whether it can be deleted all existing ID in my forum?
@weBex pleaseee
Mark Billy Wrote:Please 
There's nothing I can do, I don't have any control of your host.
Contact them.
if you want to return again how?
Can you please be more explicit? We cannot help you if we don't know the exact problem.
P.S: If you can, post some screen shots as well.
You can make a support ticket they'll reply you if they have backup of your forum
admin on my forum to switch to another user
and user's error
if the click to the links is a pain!
How about providing us a link to your forum?
powercyber.tk
There's a picture of the admin username tp if the click error