Is there a successor to The Legend of Korra or a new Avatar series in general?

I know Netflix will soon have an avatar series that will probably show the series "The last Airbender" with real actors again and now I wanted to ask whether a release date has been announced or a successor to Korra has been announced. L

Nope the makers are currently silent. You haven't ruled out a sequel but haven't said anything yet.

Not from Netflix either?

If you want to know what's going on with Aang or Korra, there's a comic series of both.

From Lord of the Elements there are currently 3 or 4 volumes of the creators, each with 3 comics, from Korra there's currently only one volume with 3 comics.

With Lord of the Elements you can learn, for example, how things will go after the war, Zuko becomes a fire lord, republics are gradually founded, etc.

At Korra it starts with the Korra returning from the spirit world and not everyone is pleased that the portals have appeared in the spirit world.

A real film / series by Netflix is expected to be produced from 2020
https://www.futurezone.de/streaming/article226968661/Avatar-der-Herr-der-Elemente-Netflix-kuendigt-Neuauflegung-der-Serie-an.html