Plus how should I use a multimeter to test it.
P. S. Really sorry for a noon question
I assume that all the servos are identical, so it is enough to measure only one, and multiply the result by 9.
The best would be if you could use a lab bench variable power supply, like this. With one of these you do not even need a multimeter as these power supplies are able to measure the current they are sourcing. You simply just need to connect the "+" to the VCC of the servo and the "-" to the GND of the servo, set the output votlage and check the current.
If you do not have access to such a device then the following setup should be used.
As you can see the multimeter should be connected in series with the servo to measure its current.
You should connect to multimeter cables as it can be seen on the following image.
You are going to measure DC current, and possibly it will be over 1 A, so choose the measurement range accordingly. The red cable goes to the power supply Vout ("+") and the black cable goes to the VCC of the servo.
Make sure the all of your wires are suitable for the measurement, they won't melt or catch fire because of large currents. And if exists, check the datasheet of the servos about its current comsuption, just to know what range to expect.