Can somebody please tell me where I would find the password for the warehouse..

You will get the first password by battling the rockets in front of the ember cave and you will get the second password by obtaning the Sapphire gem then a scientist will take it from you and give you the second password.

Go to island 6 and use Cut on the cave door at the ruins

The 2nd password is gotten in 6Island Dotted Hole in the ruins.

You have to go to island 6, and go inside the cave with the steel door and get the Sapphire, and a sincetist will steal the Sapphire from you and give you the password to the ware house, oh and also use Cut on the steel door.

Go get the Sapphire and a Scientist will snatch it from you, giving you the second password.

You will find the password at the scientist but I forgot where to get the other password

Go to the 6th island with a pkm that knows Cut and find a structure with a braile door and use cut on it. Once inside, go down the ladder or whatever there is and you'll be facing a braile tablet, it says UP, so go to the hole in the room and fall through, the next hole will be the on the LEFT, then the RIGHT, and last but not least go DOWN and you'll find the Sapphire gemstone, but a scientist guy will come following you and steal it and he'll tell you the second password to get in the Team Rocket Warehouse.