Does harry potter become lord Voldemort?

Answer 1

No, he doesn't. The two have a very complicated relationship (see below for details) but they each stay their own beings.

Harry's wand and Voldemort's wand share the same "core" - that is, the phoenix that provided the feather for Voldemort's wand dropped two feathers - one of which ended up in the core of Harry's wand, and the other in the core of Voldemort's wand. This provided Harry with the protection of the twin cores - which is never fully explained in the book. Their wands often connect - in short, Voldemort can't touch Harry with his own wand since Harry has the protection of the twin cores.

Another relationship is their blood. Harry's mother, when she died, performed old magic - the protection of love. Harry was protected by his mother's love, and Voldemort could not touch him when he had that protection. But in the Goblet of Fire, when Voldemort returns, he uses Harry's blood in the potion. Harry's blood now runs in Voldemort's veins - along with the protection from Lily Potter. Now, Voldemort can touch him.

The third and most important relationship is that, on the night he killed Harry's parents and failed to kill Harry, Voldemort accidentally created a seventh Horcrux, which latched itself onto the only living thing it could find - Harry. So though Harry had a bit of Voldemort's soul in him, Harry was still Harry.

Despite these connections, Harry never turned into Lord Voldemort