
Does YJH of the current of 3rd regression have memories of his future regressions? Does he know that he will have to go through more than a hundred regressions?

No, he doesn't know the things Dokja read.
More than that, 3rd regression yjh is still hopeful, he's not yet the battered man of the latter turns that dokja knows. This man still believes he can reach an end where he saves the most people, so not only he doesn't know he went/will go through hundreds of turns, he doesn't even expect to. He doesn't expect to fail that much, to lose so much.
He doesn't even remember the 0 turn, so the future regressions are completely out of reach for the current him. All he knows is the 1st, 2nd and the current regressions.
Yjh (and this whole turn) is different from what Dokja read in Ways of Survival because of dokja's interferences as well as the fact that a character in a book is only a side of him, and not him as a whole. BUT, like the comment above said, there are inconsistencies in his memories, and that too holds a lot of weight on why he is different.
Oh, dear, you're in for a ride.

Any spoilers? Is she able to do martial arts?

SPOILER:
Yes! Although her Qi center was broken, she received a new type of power (the one the Divine Physician gave her) and it basically allows her to control the Qi particles in the environment instead of her getting the Qi from her center.
She first lets her father and grandfather know by creating a Soundless Barrier bubble (which is basically more advanced that Sword Qi) so they were really excited and got carried away. Her dad became her teacher (in the past life story, he was supposed to teach the ML).
It's about to go down