Word to EPUB Conversion with TOC

I have a finished Word manuscript that contains straightforward text plus a separate front-cover and back-cover page. What I now need is a clean, standards-compliant EPUB version that preserves the covers exactly as supplied and includes a fully clickable table of contents.

The job is simple but I want it done professionally: no unwanted styling, correct paragraph structure, embedded fonts if necessary, and a navigation pane that mirrors my chapter headings. Please use any tool you are comfortable with—Sigil, Calibre, InDesign, or an equivalent—but the final file must pass epubcheck without errors and display properly in Apple Books, Kindle Previewer, and common Android readers.

Deliverables
• One validated .epub file with working internal links and metadata
• A short note on the conversion process so I can reproduce minor edits in the future

If you have recent examples of similar conversions, feel free to mention them; otherwise I look forward to receiving the finished EPUB ready for publication.