you can do the following e.g. on the console:
<code> $ indiserver --version
2021-04-29T10:43:59: startup: indiserver --version
Usage: indiserver [options] driver [driver ...]
Purpose: server for local and remote INDI drivers
INDI Library: 1.9.0
Code v1.9.0. Protocol 1.7.
...</code>
or
<code>$ dpkg --list | grep libindi
ii libindi-data 1.9.0 all Instrument-Neutral Device Interface library -- shared data
ii libindi-dev 1.9.0 amd64 Instrument-Neutral Device Interface library -- development files
ii libindi1:amd64 1.9.0 amd64 Instrument-Neutral Device Interface library -- shared library
</code>