VOICELESS ADVANCED UVULAR UNASPIRATED PLOSIVE [q̟]
Tiberian Hebrew qof does not have a corresponding sound in English. It is a bit like Arabic qāf, but its place of articulation is slightly more forward in the mouth. It may help to think of where you pronounce gimal rafe גֿ [ʁ] and kaf rafe [χ], on one hand, and where you pronounce gimel with dagesh גּ [g] and kaf with dagesh [kʰ], on the other. Tiberian qof is pronounced right in between these two pairs of sounds as a hard plosive/stop sound. For those familiar with Arabic, it is pronounced similarly to the letter qāf (ق), but slightly further forward in the mouth.
SOURCES AND FURTHER READING
Khan, Geoffrey. 2020. The Tiberian Pronunciation Tradition of Biblical Hebrew. Cambridge: Cambridge and Open Book Publishers. §I.1.19.