All Windows based computers comes with a pre-installed Administrator account and a Guest account. By default those accounts are disabled for security purpose.
Guest users are people you allow to use your computer for basic things like accessing the internet, checking emails and such. To enable guest account:
1. Simultaneously press the Windows key + R to open the Run Window, here type lusrmgr.msc and press Enter.
2. From the left pane select Users folder.
3. Then Double-click on the Guest account from the right.
4. In the properties window for the Guest account, uncheck the checkbox labeled Account is disabled and then click on the Apply button.
Log out and you’ll see the guest account available, now you are able to let others access your PC as guest. Keep in mind not to leave the account always enabled due to security issues.