When you dial your own phone number it should bring you into the Voicemail system.

If you've never set it up then it will give you prompts to do so.

Here are instructions to setup your voicemail

https://www.koodomobile.com/help/voicemail

Thanks but when I call my cell number it says busy and hangs up.

Weird. 

What happens when you press and hold 1?

Perhaps you disabled your voicemail feature. As a result, you may need to contact a Koodo rep to have them enable it on their end before you can set it up. Either schedule a callback through Koodo Assist or send a message on Facebook Messenger or Twitter. https://Koo.do/Chat 

Thanks everyone, it in there I pushed 1 and it said to put in my password, I have forgotten it. I am contacting a Koodo tech, thanks again. 

You can reset your voicemail password based on the instructions here

https://www.koodomobile.com/help/voicemail

After resetting your voicemail password, there’s also the option of turning off or bypassing the voicemail password, if you want to. From the main voicemail menu, select 4 (Personal Options) then select 8 (Bypass Password On/Off). 

I highly recommend you ALWAYS require a voicemail PIN. I have personally confirmed that Koodo’s voicemail system blindly trusts the caller ID, so if someone else calls the voicemail access numbers with your fake caller ID, they are immediately logged into your mailbox and can listen to your messages, changes settings, etc.