Need to install new HDD in macbook pro, do not have installation disk, can this be done?
Follow this:
https://support.apple.com/en-us/HT201372

Install the new internal HD.

Connect the installer drive and boot. It should automatically boot from the installer drive if it doesn't find a bootable OS X on the internal drive. If it doesn't, hold the Option key when you boot. It will boot into the OS X installer. You will figure it our from there.