Hi Everybody

,
If im using 15mm MDF board for the said of an arcade cabinet, and I intend to T-Mold the edges, I understand I need to use a router for this, which my dad has.
Can anybody please tell me what router 'bit' I need to purchase to create the groove in the MDF?
Im not exactly sure of the thickness of the T-Molding piece which locks into the wood, but it looks around 3mm? so if that's the case, the router bit needs to leave 6mm, then gouge out a 3mm section?
I am not a wood-work person at all, so apologies if this question looks dumb.
Kind regards,