Will i lose pictures after I do an iPhone the store?

If you mean an iPhone "restore to factory settings", then yes, you'll lose all data, apps, pictures, media that are on your device.

Create a full backup of your device in advance:--> How to back up your iPhone, iPad, and iPod touch – Apple Support

before performing this procedure:--> Restore your iPhone, iPad, or iPod to factory settings – Apple Support

If you mean something different, please better specify your needs.

Regards

Giulio

if you restore it to factory settings then you will lose those not stored in icloud

A restore will erase all content from the phone.

If you restore from a backup, the contents of the phone will be replaced by the data in the backup.