Plone 6 Volto Is that possible to shadow the default contact-form for notfound

Is that possible to shadow the default contact-form i.e forward it to a form block.

or I should edit /frontend/core/packages/volto/src/components/theme/NotFound/NotFound.jsx

every time when plone update?

Never edit core code, unless you're contributing to it.

Follow the best practice of creating a new or developing an existing add-on, as described in the section Develop Volto add-ons — Plone Documentation v6 in Plone 6 documentation.

This allows you to release your add-on to a package registry, such as npm.js, and install it wherever you like. What could be easier? You could even have multiple versions of your add-on that each depend on current or future versions of Volto, and pinning your project's dependencies.