We hope that this response reaches you in the best of health and Imaan. Ameen.
Surah Kahf is indeed to be recited on Friday and is said to be a means of protecting oneself against Dajjal. It is best to recite the entirety of Surah Kahf, but if there is some shortage of time, etc. one shoudl read the first ruku and last ruku of the surah.
And Allah knows best.
Ask Alimah Team
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