I believe the paypal must be send as a gift.
You mean you should lie to PayPal to get them to do something they wouldn't do if they knew the truth? Really?
Can be gift charged back?
If you are asking if the payment can be reversed, of course it can. The sender just has to say they didn't authorize the payment and PayPal will reverse it. Gifts are the easiest to reverse -- for what possible dishonest reason would a person want to reverse a gift? There are clear reasons to dishonestly try to reverse a payment, but surely someone who wants to reverse a gift is almost certainly telling the truth when they say it's unauthorized.