Leave Minecraft without a trace?

At the first spawn in the Nether I spawned UNDER the lava and if I build a portal somewhere else, I will always teleport to the SAME portal UNDER THE LAVA. Can you somehow leave the nether so that you spawn completely NEW the next time you visit?

First dismantle the old and build the new one nearby in a safe place.

In order to build a second portal in the Nether, the portal on the surface must be at least 1025 blocks away from the next one.

The old one in the upper world or in the nether?

The old one in the Nether.