|Not sure what you mean systems password. |
There are a few ways to improve the physical access security of a computer. Most revolve around disk or partial disk encryption. Both MS and third party apps can do that.
Be warned that if you are silly enough to forget the correct password the data may be rendered useless.
Some of the newer laptops can be protected in a very good way. If you don't have the correct password the unit needs to be shipped back to a repair facility.
A Pit Bull is like a gun you can pet. And there is no safety on it.