Qu'ran mentions this mysterious wise man sage Al Khidr and his story with Moses, and there is mention of "fountain of life" that he drank from, so is he alive forever to this day? If he is, is he hidden? Can you provide some hadith or tafsir narrations on this subject what do the scholars say?!
Firstly, there is no evidence of him drinking from fountain of life or anything, neither have you provided.
And against this:
“And We granted not to any human being immortality before you (O Muhammad); then if you die, would they live forever?” [al-Anbiya’ 21:34]
And Their is no evidence to declare him immortal, so no one can say if he is alive. So, lack of any evidence clearly decides whats probable. He is not alive, nor had he been to fountain of life and no one knows if this kind fo thing even exists...