I write a lot of README.md files for technical stuff. Assuming you have the cSpell extension installed, you'll get a lot of blue squiggles. These spelling errors occur because the cSpell only understands your language, not your programming language. So, you need to tell it the spelling is correct by adding the work to the cSpell dictionary.
Let's say we include the commmand
chmod in a file. A squiggle will show up. Highlight it then press
The resulting menu includes
Add: "chmod" to workspace directory. Select it and press enter.
I like to use the workspace file to store these exceptions because they are often project specific. You can add words to the user dictionary if you want it to be used across workspaces.