The name Selena in Hebrew letters is סלנה. Below: how its number adds up, which page of the Torah it falls on and what verse stands there. Everything is computed, nothing is guessed.
סלנה
In short
Your name in Hebrew letters is סלנה. From Greek Selene, “moon”, the name of the moon goddess in Greek myth. The chemical element selenium is named after the same word. In Hebrew it is written by sound. Adding up the numbers of its letters gives 145 — the same as the Torah word יפנה, “Jephunneh, father of Caleb”. That number points to Torah page 145 of 354 — in the portion Ki Tisa. What that portion is about: The half-shekel for the census; the golden calf and the broken tablets; the thirteen attributes of mercy; the second tablets. The verse that begins with the first letter of your name and ends with the last is Numbers 14:19. Each of these steps is laid out below with its sources. Every figure can be checked by hand.
You wrote “Selena” — this exact spelling is what was calculated: סלנה. A name from the Tanakh — its Tanakh spelling is used. If your name is spelled differently, correct the Hebrew spelling and the report is recomputed.
Adding up the letters of the name סלנה gives 145.
145
The number 145 is the Torah word יפנה — «Jephunneh, father of Caleb» (Numbers 13:6).
And Aaron and his sons shall wash their hands and their feet thereat;
This is from the portion Ki Tisa. What it is about: The half-shekel for the census; the golden calf and the broken tablets; the thirteen attributes of mercy; the second tablets.
Other ways of counting
The tradition counts the same name in several ways. The main one is above: each letter is its number. The other eight are old and checkable too; each gives its own number, and many of them have a Torah word with the same number.
Final letters as 500–900 (mispar gadol) — 145. A Torah word with the same number is יפנה — “Jephunneh, father of Caleb” (Numbers 13:6).
Reduced, each letter to one digit (mispar katan) — 19. A Torah word with the same number is גוי — “nation” (Genesis 10:5).
Ordinal: alef 1, bet 2 … tav 22 (mispar siduri) — 46. A Torah word with the same number is מאה — “hundred” (Genesis 5:3).
Cumulative: a letter plus all letters before it (mispar kidmi) — 570. A Torah word with the same number is עשר — “ten” (Genesis 5:8).
Squares of the letter values (mispar perati) — 7025.
Building: the sum grows with each letter (mispar bone’eh) — 435. A Torah word with the same number is תלה — “to hang” (Genesis 40:19).
The letters that come out are חכטצ — not a word that stands in the Pentateuch. Atbash: letters mirrored, alef for tav, bet for shin, and the number of the resulting word — 127. A Torah word with the same number is נמואל — “Nemuel, a Reubenite” (Numbers 26:9).
Filling: the names of the letters are counted — alef, bet, gimel… (milui) — 306. A Torah word with the same number is אשה — “woman, wife” (Genesis 2:22).
The number 145 appears in the classical books 5 times across 4 works. The earliest mention is טור ברקת (~1650).
Every letter of the name explained, the words and namesakes with references, the Hebrew date, the letter and tribe of the month, day 861 of your life (±1), the psalm by age, the attestations from the classical books — a PDF sent to your email.
The number of the day, every morning
Every date has a number too. Once a year it will match the number of your name — 145. The channel posts one number a day, one verse and the Torah page it lands on. Nothing after it, no mailing list.
Hebrew is written from right to left. סלנה has 4 letters: ס Samekh, ל Lamed, נ Nun, ה He. The first letter is Samekh, the last is He.
For an engraving, a sign or a tattoo, show the spelling to someone who reads Hebrew: transliterating a name is a choice, not the only option.
The name סלנה does not stand as a word in the Pentateuch — as with most names, including many Tanakh names from the later books.
The verse of your name
There is a custom: at the end of the prayer one says a Torah verse that begins with the first letter of one's name and ends with its last. For סלנה these are ס and ה. The Pentateuch has exactly one such verse — Numbers 14:19:
סלח נא לעון העם הזה כגדל חסדך וכאשר נשאתה לעם הזה ממצרים ועד הנה
This is from the portion Shlach. What it is about: The twelve spies; forty years for forty days; challah and tzitzit.
Each Hebrew letter has a number; a word's number is their sum (alef 1 … tav 400). The page is the remainder modulo 354: the Torah divided into 354 pages of 861 letters, as the lunar year has 354 days. Everything can be checked by hand.