to the part:
To confirm that the 1DBA2E89 admin@f-droid.org PGP key is trusted by the index JAR signing key that is built into the F-Droid client app, run these commands:
I entered the following commands to terminal/got communicatate:
(system name):~$ sudo apt-get install wget vim-common unzip openjdk-8-jdk-headless wget https://f-droid.org/assets/admin@f-droid.org.jar
[sudo] password for (system name):
Reading package lists… Done
Building dependency tree
Reading state information… Done
Package unzip is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
We trust you have received the usual lecture from the local System
Administrator. It usually boils down to these three things:
#1) Respect the privacy of others.
#2) Think before you type.
#3) With great power comes great responsibility.
Reading package lists… Done
Building dependency tree
Reading state information… Done
Package unzip is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package ‘unzip’ has no installation candidate
E: Unable to locate package openjdk-8-jdk-headless
Second command (wget) seems ok, but this one not.
Similar 3rd command (git clone)
(system name):~$ git clone https://gitlab.com/fdroid/fdroidclient
Cloning into 'fdroidclient'...
fatal: unable to access 'https://gitlab.com/fdroid/fdroidclient/': The requested URL returned error: 403