You’re looking for
tomcat/bin/catalina.sh run
instead of
tomcat/bin/startup.sh; tail -f tomcat/logs/catalina.out
Tomcat stays in foreground this way (first option). If you want to shut it down, Ctrl-C in your console window will do the trick.
If you choose the second option, tomcat will run in background, while tail will run in foreground, but you’ll have to give the same directory path twice.