@CharleyL has made some very valid points, and especially about the need to understand the principles of lighting.
But, although umbrellas can be a very useful lighting tool, they can be a very blunt one too; the shoot through umbrellas spread light everywhere, creating (often) unwanted light spill just about everywhere, and the smaller the shooting space, the lower the ceiling and the lighter the walls and ceiling are, the blunter that tool becomes.
The reflective umbrellas he mentioned don't spill as much light, but because they are reflective and so have to face away from the subject, they can't be placed close and therefore cannot, if required, produce a really soft light.
Softboxes combine the benefits of both shoot-through and reflective umbrellas, with none of their downsides. Godox don't make the worst softboxes, but they're average at best.
I can't recomment any specific makes, but make sure that you get one that has two diffusers, make sure that the inner diffuser sits well back from the outer diffuser, and that it's very nearly touching the inner walls of the softbox, make sure that the front diffuser is deeply recessed, make sure that the seller also sells replacement diffusers, because they all yellow over time and need to be replaced and - although more difficult when buying online than when physically viewing them, make sure that the diffusers are sturdy, thick and so actually do their job.