Could you please elaborate?

The header looks undersized, dayligh showing, no tapered sill. Not sure why there is extra jack stud on one side and 2 on the bottom and off centered. You getting this inspected? Lots of odd things in 1 window opening. If it was structually sound before adding lumber won’t change that.

Other than the smallish header, it's ok. You must not get snow.

Cheesy method but at the end of the day as mentioned above, if it were structurally sound before it will be now as well. But that would typically be a 6" header, so there is that.

Can you add a picture from the outside that gets bigger when you click on it?

The header looks to me like 2- 2"x4" or possibly a single 4"x4". And, yes, there should be a strip of OSB added on the outside.

If this is a custom build, ask your builder/manager/GC or look at the plans.

Probably no header required.