To try it head out, head here and click the 'Start Windows 95' button. Be warned the disk image is 131MB uncompressed, so it will take a few minutes to load on an average connection, and even once loaded, it will probably run slower than you remember for a variety of technical reasons. Once you're in, click the Fullscreen button to gain control of the OS.
Windows 95 launched 20 years ago and was a landmark OS for Microsoft. Support for it ended just a day prior to 2002.