Let’s learn Surah Kahaf’s first 10 verses (last 10verses as well, according to one narration but since first ten verses are mentioned more often so we will take baby steps for now and in shaa Allah after that we can strive to memorize the last ten verses as well).
1) Because Prophet (saws) asked us to
He only asked us to do what he did himself. So consider it as a sunnah as well (not just the way of prophet (saw) but of so many companions, successors and so on).
I have never come across memorization of any specific surah/ayaat except for this.
“If anyone learns by heart the first ten verses of the Surah al-Kahf, he will be protected from the Dajjal.” [Muslim]
Though memorization of some surahs is just plain obvious (like Surah Fatiha for the validation of your prayer), but Surah Kahaf’s memorization has been specifically talked about.
Since Prophet (saws) was so concerned about us (as mentioned in the sixth verse), following his advice is the least we can do…