How to execute script in Script Manager

Under Editor, I selected ‘Load and Execute a Script File’. This is what came up in Script Manager;

SET LINESIZE 150;
SET PAGESIZE 0;
set heading off echo off feedback off;
SPOOL C:\temp
select table_name
from all_tables
where owner = ‘SCOTT’;
spool off;
set heading on echo on feedback on;

How do I execute it?

Looks like a SQLPlus script, which Toad still supports. Use the SQLPlus mode of the overloaded script execution icon. See screen capture below.