want to start a random links in cmd script

hello I'm trying to run this script:

SET 0=http://www.zap.co.il/    
SET 1=https://sa.zap.co.il/    
SET 2=https://vpc.must.co.il/bo1/MainForm.asp   
SET 3=https://direct-israline.co.il    `enter code here`
SET 4=https://mypost.israelpost.co.il

setlocal EnableDelayedExpansion

for /l %%x in (1, 1, 5) do (
    SET /a link=!RANDOM! %%5
    start !link!
    set /a num=!RANDOM! %%20+5
    TIMEOUT !num! /nobreak
)

but it won't run...

can anyone help?