(fix #684): Fixed all the typos and grammatical errors.

[subhamkumarr]

Fixes: fixed all the grammatical and typos errors in the interactive book.

- All spelling is checked by Grammarly before making any changes in the code.

✅️ By submitting this PR, I have verified the following

• [X] Checked to see if a similar PR has already been opened 🤔️
• [X] Reviewed the contributing guidelines 🔍️
• [X] Sample preview link added (add the link(s) for all the pages changed/updated from the checks tab after checks complete)
• [X] Tried Squashing the commits into one

[subhamkumarr]

@tanmoysrt @tachyons Could you please my PR.