How to erase data on mbp?

[warplane95]

I, tomorow i'll return my macbook pro to staples canada.

I want to erase all my data, but i didnt want to erase the os? how can i do that?

 

[Gav2k]

Cmd + r when powering up and select restore

 

[benwiggy]

Deleting everything in the User account, including the Library folder, which is normally invisible, should suffice.

 

[Weaselboy]

I, tomorow i'll return my macbook pro to staples canada.

I want to erase all my data, but i didnt want to erase the os? how can i do that?

Create a new, admin user account and login to that account. Now from that account delete your old account. Unless you have placed personal data in non-default locations that will remove everything.