Smooth structural plaster

Hello everyone,

we have initially sporadically reroofed the roof of our shed, the old one had collapsed when we bought the property. I attached a picture for you: Is it possible to smooth this plaster? Or to even out the broken spots at the upper edge? We would like neat and smooth plaster, like the kind usually found on single-family houses nowadays. Even though there also seems to be a slight texture in it.

If anyone wants to criticize something about the roof: the material was free, and since we are not yet 100% sure whether the whole shed or only a part of it can remain (due to [Grenzbebauung]), we have decided to initially roof it only sporadically, so that we can store something underneath. Once it is clear what can remain, the roof will be properly done.

Image is coming shortly. File is always too large.

Here is the picture

A bit small, but unfortunately the image size is limited.

No one has an idea or is an expert

Do you want to repair only the top edge now or smooth the entire wall instead of the wavy plaster?

Best regards in short