Hi there, so I have to say, I never worked with Linux before so everything I did was following some tutorials.
So first I did this: https://www.javahelps.com/2015/03/install-oracle-jdk-in-ubuntu.html , but I replaced the JDK with JRE8 Update 231. Worked, java -version showed me the correct version.
Then, I followed https://confluence.atlassian.com/adminjiraserver/installing-jira-applications-on-linux-938846841.html and tried to start up the service, however, I'm greeted with this:

I already tried increasing the max. memory but that didn't quite work. Also I do not fully understand the support article I'm being linked to, I'm a pretty new user and only know the basics, a former Windows installation went perfectly fine, but I want to migrate servers.
Any help would be appreciated, I spent almost 4 hours googling for solutions but nothing helped so far.
Also, here's a pastebin of the catalina.out log: https://pastebin.com/ERN0EM4s