The sql script you indicate is trying to run several other sql scripts it expects to find in a directory structure like this
run.sql (your script above)
/tables
run.sql
/sequences
run.sql
/views
run.sql
/functions
run.sql
/procedures
run.sql
You dont mention if you are on a windows machine or unix/linux. If you are on unix/linux, normally you would use the sqlplus command line to run this script from the directory containing the top level run.sql (the one containing the commands you listed above).
PLSQL developer will run on windows so I assume it will use whichever directory is set as the "location" on the windows properties that you use to start plsql developer (probably something like c:\Program Files\plsqldev as a default so to find the scripts, it would expect the subdirectories (procedures/tables/view/sequences etc..) to be under that directory.
You will need all the scripts and to keep the subdirectory structure on either your windows client machine where plsql developer is running or on the database server where the Oracle database resides in order to run the script you have indicated above.