How do i open my macbook air... i can remember the password

Reset Computer Password  for the Administrator Account Password

Intel Computer

1 - Shutdown the computer 

1A - Restart computer and immediately hold the two keyboard combo Command  r 

1B - If using a Bluetooth Keyboard with Rechargeable Battery - Cable the Keyboard to computer for this unique purpose. Bluetooth Kernel may not load soon enough to execute the 2 keyboard commands 

2 - Top Tool Bar >> Utilities >> Terminal

3 - Type resetpassword as one word and no spaces

4 - Press Return key

5 - Follow the prompts and remember the New Password

Type in the password followed by the return key.