The age of X-23 in the comics isn't fixed. It can change based on the narrative and continuity. Sometimes she's shown as a young adult, but it really depends on the context of the story being told.
It depends on the specific comic series and storyline. In some, he's alive and playing a significant role, while in others, his fate might be different.
Professor X's fate varies in the comics. Sometimes he does die, but comic writers often find ways to bring characters back or explore alternate timelines where his survival is possible.