Is it possible for a level 29 to hit level 60/70/80s with a high amount of attack rating gear? Is this the main stat that controls that?

Bump

Level 20 char has max 40% chance to hit lvl 80. You cannot surpass the level difference penalty.

Chance to hit is calculated like this: https://diablo-archive.fandom.com/wiki/Attack_Rating_(Diablo_II)

In short: 2 * your lvl / ( your lvl + enemy lvl) is the maximum chance you can get. There are skills that always hit though, like smite, spells and lightning fury (his one can be blocked though).

The 40% max is with hitting the AR cap correct? Without AR how much lower does the hit % go?

Check the formula in the link.