This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
臸 visually doubles the component 至, but the exact historical development is uncertain. It may have been created to express an idea related to reaching or arriving, but no clear meaning is preserved.
Two 至 components side by side suggest something like 'reaching repeatedly' or 'arriving together,' but the actual meaning is unclear. Treat it as a rare kanji with an uncertain meaning.
For ジツ, imagine two identical 至 blocks clicking together with a sharp 'jitsu' sound, like a puzzle piece snapping into place.