echo

how can you remove a echo from your recordings on audacity?

Short answer: You can’t.

The problem is that if you have, for example a voice recording, and it has an echo, the computer has no way to know what is “direct” voice and what is “echo”.

Longer answer:

There are a couple of advanced AI based solutions to the problem that are being developed, but are not (yet) available in Audacity.
See: https://help.krisp.ai/hc/en-us/articles/360017039059-Echo-cancellation-with-Krisp-on-Windows
(The other best known example is “nvidia RTX Voice”, but that requires specific nvidia hardware)