install synaptic

 sudo apt install synaptic
[sudo] password for dhwan:
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following package was automatically installed and is no longer required:
  libfprint-2-tod1
Use 'sudo apt autoremove' to remove it.
The following additional packages will be installed:
  libept1.6.0 libxapian30
Suggested packages:
  xapian-tools dwww menu deborphan apt-xapian-index tasksel
The following NEW packages will be installed:
  libept1.6.0 libxapian30 synaptic
0 upgraded, 3 newly installed, 0 to remove and 0 not upgraded.
Need to get 1.362 kB of archives.
After this operation, 6.346 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://id.archive.ubuntu.com/ubuntu focal/universe amd64 libept1.6.0 amd64 1.1+nmu3ubuntu3 [79,6 kB]
Get:2 http://id.archive.ubuntu.com/ubuntu focal/universe amd64 libxapian30 amd64 1.4.14-2 [661 kB]
Get:3 http://id.archive.ubuntu.com/ubuntu focal/universe amd64 synaptic amd64 0.84.6ubuntu5 [622 kB]
Fetched 1.362 kB in 7s (191 kB/s)                                              
Selecting previously unselected package libept1.6.0:amd64.
(Reading database ... 183329 files and directories currently installed.)
Preparing to unpack .../libept1.6.0_1.1+nmu3ubuntu3_amd64.deb ...
Unpacking libept1.6.0:amd64 (1.1+nmu3ubuntu3) ...
Selecting previously unselected package libxapian30:amd64.
Preparing to unpack .../libxapian30_1.4.14-2_amd64.deb ...
Unpacking libxapian30:amd64 (1.4.14-2) ...
Selecting previously unselected package synaptic.
Preparing to unpack .../synaptic_0.84.6ubuntu5_amd64.deb ...
Unpacking synaptic (0.84.6ubuntu5) ...
Setting up libxapian30:amd64 (1.4.14-2) ...
Setting up libept1.6.0:amd64 (1.1+nmu3ubuntu3) ...
Setting up synaptic (0.84.6ubuntu5) ...
Processing triggers for desktop-file-utils (0.24-1ubuntu3) ...
Processing triggers for mime-support (3.64ubuntu1) ...
Processing triggers for hicolor-icon-theme (0.17-2) ...
Processing triggers for gnome-menus (3.36.0-1ubuntu1) ...
Processing triggers for libc-bin (2.31-0ubuntu9.1) ...
Processing triggers for man-db (2.9.1-1) ...
Processing triggers for bamfdaemon (0.5.3+18.04.20180207.2-0ubuntu2) ...
Rebuilding /usr/share/applications/bamf-2.index...