The recommended way to use Eelbrain is in a separate Conda environment. First, install the Anacond Python distribution. Then, create an environment file with the libraries you need (for example, use this environment.yml as a starting point), and create the environment:
$ conda env create --file=environment.yml
Eelbrain in an existing environment can generally be updated with the following command (assuming the target environment is currently active):
(eelbrain) $ conda update -c conda-forge eelbrain
Sometimes Conda will run into difficulties while updating and it may be easier to create a new environment instead.
If you often create or update environments, use Mamba as replacement for Conda.
For other ways of installing Eelbrain, see this wiki page.