No. Windows 7 is not like a service pack. It is a different version of Windows. You must purchase a retail Upgrade or Full License copy of Windows 7 in order to upgrade from Vista to Windows 7. Use the Microsoft Store online
There was a free Upgrade from Vista to Windows 7 for Computers and Software bought within a certain time frame, but that offer finished at the end of Jan 2010.
Before you spend your money you should see if your Computer is capable of running Windows 7.
Download and run the Windows 7 Upgrade Advisor to see if your PC is ready for Windows 7. It scans your hardware, devices, and installed programs for known compatibility issues, gives you guidance on how to resolve potential issues found, and recommends what
to do before you upgrade.