What Hebrew text is equivalent to the New Testament?

There is none. The Hebrew Bible, or "Tanakh" (תנ״ך) only contains the books that Christians refer to as "the Old Testament." But the Old testament is not at all equivalent to the New Testament. Both have entirely different information and messages.

The New Testament was written in Greek only.

There is an online version of the New Testament in Hebrew, but its quality is mediocre both in translation and in layout, and there are numbering mistakes throughout (verses are mislabeled in the Hebrew side, so the English verse doesn't alway match up to the correct Hebrew verse. you can view it here