ttctools is a dedicated tool for handling TTC fonts. It can split a TTC file into multiple TTF files or combine several TTF files into a single TTC. For 64‑bit Windows systems, the version called is the most up‑to‑date choice. Both 32‑bit and 64‑bit versions are available.
TTC (TrueType Collection) file is a single package that contains multiple TTF (TrueType Font) convert ttc font to ttf work
Or with the classic BREAKTTC utility: