How "covered" are you looking to get?

You can use a window film, or a frost spray if you are just looking to block out the window.

some sort of seasonal decor/wreath?

Maybe you could replicate the panels below it but horizontally with something like inexpensive luan and some trim pieces. Would probably require painting the door though. Any DIY carpentry skills?

I might try to frost it or use some window film. All good options.

I dont have carpentry skills but im against trying something different.

Where did you get that door??

" Where did you get that door?? "

@William Warner, any real lumber yard can order that door, it is a very common door style.