Help! My Orchid's Leaves Are Falling

[Orchidus]

Hello plant friends,

I hope you can help me because my orchid seems to be very sick at the moment. Until recently, it looked quite healthy, but now its green leaves are suddenly falling off, and the stem (the part where the leaves are attached) looks like it’s rotting? The leaves themselves have some white spots that look like a coating (I suspect these might be pests).

Here are a few details about my orchid:

The roots are mostly still green and firm.
The stem looks as if it’s burned or rotting.
There are white, slightly cottony spots on the leaves (maybe mealybugs?).
The leaves are turning yellow at the base and then just falling off.

My questions for you:

Is the orchid still savable, even though the stem is rotting but the roots are still healthy?
How can I make sure that the white spots (if they are mealybugs) disappear for good?
Do you have any tips on how I can best care for the plant after this treatment so that it can recover?
Is it possible to make a cutting or propagation from the green, healthy roots if all the leaves fall off?

I look forward to your advice and tips!

Thanks in advance! 😊