PLEASE anyone can suggest me right tutorial for installing freepbx?

Which operating system is best for asterisk and freepbx?
Which asterisk version is working?
Which freepbx version is working?

I am tired of downloading and installing asterisk and freepbx.
I am applying the exactly the same steps with this link:
http://wiki.freepbx.org/display/FOP/Installing+FreePBX+12+on+CentOS+6.5

But still does not work.PLEASE anyone can help me?

FreePBX Distro is the easiest way for a fresh start.

You can start with a stable version 6.12.65

Thanks for your advice. But i want to download and install asterisk and freepbx myself. Now please can you advice me at right operation system and right installation tutorial?

The link you posted is what we would advise.

Now i have one problem. I have solved %90.
When i click “Asterisk Modules” under Admin menu. There are 3 options unde Asterisk Modules, these are Excluded Modules, Preloaded Modules and Manually loaded modules.
First there is not chan_sip.so module under this menu.
Second , when i click “add” button any of these 3 options so i get this error message.
FATAL ERROR
FreePBX is Unable to Continue
Wasn’t given a module to preload
Trace Back
/var/www/html/admin/modules/core/Core.class.php:66 ModulesConf->preload()
[0]:

/var/www/html/admin/libraries/BMO/GuiHooks.class.php:281 FreePBX\modules\Core->doConfigPageInit()
[0]: astmodules

/var/www/html/admin/libraries/BMO/GuiHooks.class.php:249 GuiHooks->doBMOConfigPage()
[0]: Core
[1]: astmodules

/var/www/html/admin/config.php:317 GuiHooks->doConfigPageInits()
[0]: astmodules
[1]:

How can i solve these 2 problems?

Any module that is not listed there is auto loaded. You shouldn’t be modifying anything there