Microsoft recently rolled out spellcheck and autocorrect functionalities in Notepad on Windows 11. Microsoft has introduced these new features nearly 40 years after the introduction of the Notepad. To recall, Notepad was included with Windows in 1983. As of this writing, the spellcheck and autocorrect are available. You should note that the integrated autocorrect is a useful productivity tool.
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The spellcheck and autocorrect features included with Notepad on Windows 11 are enabled by default. However, you can enable or disable the features for each file in Notepad for Windows 11. You need to select the Settings icon from the top right side of the Notepad. You have to scroll down to disable to features you need not require as shown below.

Notepad was upgraded with character count functionality in December 2023. You will view the required data on the status bar. Moreover, the autosave feature enables you to close the Notepad without saving the content. You can view the saved content the next time you open Notepad.