Several ways you can do this, WV.
Most laptops come with built-in mic and camera, and software to make videos. There are freebies online, too, that are better than Windows software, but the latter would work fine as well.
https://www.techsupportalert.com/
If your computer doesn’t have the built-in mic and camera, use a digital camera, if you don’t want to use your phone. It’s going to have the mic built in, and likely an easy upload to youtube, facebook, instagram, etc. Most digital cameras have built-in WiFi now, so you don’t even have to transfer the file to your computer. But you can do that as well — wirelessly or via USB cable.
You’ll need an account with YouTube, of course. Easy to set up with a google email address.
Years ago, it could be a pain in the neck to transfer files like this. Now, most cameras, desktops, laptops are already set up to “share” with all of your social media accounts.
If none of the above fits . . . and your computer has a camera but not a mic? Mics are cheap at any electronics store. Purchase one and plug it into your mic port, which is usually one of the three on the back of the computer designated for speakers or mic. If you don’t have a schema of your computer handy, look it up online and it will show you which one of the ports is used for the mic. It’s typically color-coded.