You can use a drill press to make a countersink for your drill bit
Here's how to do it
1. Place the drill bit on the spindle of your drill press, then set the spindle at a slight angle (about 15 degrees) from vertical
2. With your counterbore bit in hand, hold it so that it's facing up and use your hand to align it to the bottom of the hole you're creating in your workpiece
3. Use the handle of your drill press as a guide for depth and start drilling with the countersink bit until you reach the desired depth.
cnc drill with countersink