I would like to run a cron job through wincron everyday at 3am and also every month end there is another email that needs to be run. The application is tango and the url is something like this

http://127.0.0.1/xyz/email.taf

how can i do this

Well I'm not exactly sure what a 'tango' application is, but we can run that URL at 3AM..
Is that what you want?

# at 3AM each day
{
-name My daily email job
-start -cron * 3 * * *
-command -shell http://127.0.0.1/xyz/email.taf
}

# once each month (the 1st day at midnight)
{
-name My monthly email job
-start -cron 0 0 1 * *
-command -shell http://127.0.0.1/xyz/email.taf
}

You can put both of these jobs in your user.tg.