An entry in the process-table is a fairly insignificant thing as long as the process is not gobbling up CPU time or other resources. Proceed
carefully, and seriously consider whether to proceed at all.
Probably the most useful thing to do is to review the list of "services" (Linux calls them
daemons) which are set to run on your computer. The principle is exactly the same as "cleaning up the cruft" in a Windows installation. Many "stock distros" include a large number of running processes that you might not actually need in
your situation, because they wish to make installation as simple as possible. Perhaps
you will never run a database-server or a web-server on your box ... may never find yourself part of a Windows printer-network ... and so on. You can selectively stop those daemons and prevent them from starting the next time you boot.
I'm not going to say
how you do that, because this varies from system to system (and can in fact be accomplished in several ways depending on your personal level of technical experience).
Remember, again, to proceed carefully, and be certain that you understand
why you are taking any particular action that you take. The inter-relationship of subsystems can be

quite subtle, and the consequences of change can be

far-reaching.