[![enter image description here](https://i.imgur.com/6U0Zqx5.png)](https://i.imgur.com/6U0Zqx5.png)Need advice on how to wire everything properly. There are two wire harnesses coming into the junction box:

* H1: black(!), white, ground - comes from the fuse box
* H2: black, white, ground, red(switch) - beginning of a circuit, extending into 2 rooms on the same floor.

I am adding an electrical outlet therefore i have black wire nut with 3 black cables, white wire nut with 3 white cables, red wire nut for the switch wire and ground cables are under the screws.

If I were to add a light fixture, obviously black is going under the same wire nut with red(H2), ground goes under a screw but I am not sure where the white one goes.
From my understanding, it can go under the same white wire nut that will result in 4 wires on a same wire nut BUT i could be wrong. Still reading material but not able to put everything together when it comes to the neutral wiring.