Q: i did a backup one time but I lost every thing but know I need how to restore all my message of the whatspp from the begining

IF you lost the iPhone backup the WhatsApp info is gone as well. WhatsApp does not keep conversations in its cloud, only on your phone.

Hassania wrote:

 

... I lost every thing ...

What does this mean exactly?  You "lost" your iPhone and you lost the backup you said you made?  That would be quite a stroke of bad luck.

If you only lost the iPhone, then the WhatsApp data is on your backup.

Restore your device from an iCloud or iTunes backup - Apple Support

If you only lost the backup, then the WhatsApp data is on the iPhone.

From an iCloud or iTunes back up, you can't. Each back up only captures the current contents.