Don't worry about it. Android is very good at managing running processes automatically and efficiently for you. Attempting to control processes manually is not only a waste of time, it's actually counterproductive and wastes power.
Most apps listed as running in Settings > Apps > Running are not active. They are not using CPU cycles or power. They're only cached in RAM memory for quick retrieval if needed. For a more accurate picture of what is really going on, install System Panel:
https://forums.androidcentral.com/e?...token=TjeDgSDq
Basically, just let Android do its job for you as intended, relax and enjoy all the cool stuff your phone can do.
Android since v1.0. Linux user since 2001.