How can I do if i forgot my password and apple id,and now my device was activation lock?

You will need to bring your phone, your ID, and your sales receipt (including serial number) to any Genius Bar. If you bought your iPhone from your cellular carrier, they can help you.

See if you can recover the ID/password.

Apple ID - How to find your Apple         An iCloud e-mail address is an Apple ID.

Apple ID - Find

Enter the Apple (iCloud) ID and click Forgot Password.

Apple ID - Manage

Apple ID – Forgot Password

If it is a used phone, you will need to contact the previous owner to have them log out of iCloud or go to iCloud.com/Find My Phone and erase the device, then remove it from their account. If you can’t do that, the device is useless. 

Activation Lock - Turn off Find My iPhone