Identify the type of conditional sentence.

This is a Zero Conditional sentence, used for general truths or scientific facts. The structure is "If + present simple, present simple."

The first part, "If there is no voltage," is correct. The second part, "Can Current exists," is grammatically incorrect and does not convey the intended meaning. In electrical circuits, if there is no voltage (potential difference), there can be no current flow.

To express the scientific fact that current cannot exist without voltage, the word "Can" should be replaced with "no".

The corrected sentence is:
If there is no voltage, no current exists.

This means that the word to fill the blank or correct the sentence is no.