I have this Ubuntu version:
Distributor ID: Ubuntu Description: Ubuntu 14.04.3 LTS Release: 14.04 Codename: trusty
I just download oracle-instantclient12.2-basiclite-12.2.0.1.0-1.x86_64.rpm and install the tools using
alien -i oracle-instantclient12.2-basiclite-12.2.0.1.0-1.x86_64.rpm
But I can't find the exp anywhere, just these 2 files
root@localhost:/usr/lib/oracle/12.2/client64/bin# ls -la
total 108
drwxr-xr-x 2 root root 4096 Nov 8 14:47 .
drwxr-xr-x 4 root root 4096 Nov 8 14:47 ..
-rwxr-xr-x 1 root root 43797 Mar 16 2017 adrci
-rwxr-xr-x 1 root root 56984 Mar 16 2017 genezi
The utilities are not part of the basic (or basiclite) package. The instant client download page lists the packages and what they contain. You need to get the tools package, oracle-instantclient12.2-tools-12.2.0.1.0-1.x86_64.rpm, in addition to the basic package, to be able to use exp and imp (and their datapump equivalents; and SQL*Loader).
You may find the SQL*Plus package useful as well.