Where can I get nitrous oxide

Where can I get nitrous oxide? A lot of people don't know much about nitrous oxide, and here's the introduction to it:

Nitrous Oxide (Nitrous Oxide), also known as laughing gas, colorless gas has a sweet taste, is a kind of antioxidant, chemical formula N ₂ O, under certain conditions to support combustion (with oxygen, for laughing gas can be broken down into nitrogen and oxygen at high temperatures), but stable at room temperature, slightly anesthesia effect, and can cause person laugh. Its anesthesia was discovered in 1799 by British chemist Humphrey davey. The theory is that the n2 and the CO 2 molecules have similar structures (including electronic ones), and their spatial configurations are linear, and they are polar molecules.

It is now mainly used for performances and can also be used as a fuel booster for racing accelerators.