Hi Vmifan
To change your password you do this in your control panel.
Look at the top left of the forum screen under the area of the Home Tab for the "User CP" Stands for User Control Panel. Black letters on a white background. The 1st one in the row. Click it.
This takes you into your account control panel. Look on the left side it will say, "You Control Panel"
Scroll down the list to: Settings and Options.
In the Settings and Options group there is "Edit Email and Password" click it.
Follow the prompts on the screen to enter your new password.
If you need more help let us know.
Good luck
John