can’t remember id or passward of my iphone 6

If the phone was not properly prepared for a new user and the original Apple ID and Password used to set up the device, not properly removed, you'll need to find the original user and get their help.

If it was prepared correctly and you have simply forgotten the Apple ID and Password, use the link I provided. But note, if this is not successful, without the original purchase receipt with the iPhone serial number on it cannot be provided to Apple, Apple won't help you, nor can we.

In that case, you will need to buy a new phone as your phone will be useless to you.

Are you the one who set up this iPhone? When you say it's a gift, was it used before you got it?

If you did set up this phone originally and it wasn't used, you can try to recover your Apple ID using this link: If you forgot your Apple ID - Apple Support

If you are not the original owner and you just don't know the Apple ID and it's locked to someone else's ID, you'll need their help to be able to use the phone.