Question: How many columns are there in a סֵפֶר תּוֹרָה (Sefer Torah, Torah scroll)?

Answer: There is no fixed number!

There are a bunch of requirements, such as having at least 42 lines per column, and at least 30 letters in each line. But a Sefer Torah can end up with anywhere between 200 and 300 columns, depending on how you write it. And, for the most part, columns can end and begin wherever you want.
But there is a tradition that there are six words in the entire Torah that should always be at the top of a column. These words are described by the acronym בי"ה שמ"ו, which is a hint at writing the Torah with God’s Name in mind. R. Menahem Hameiri (Southern France, 700 years ago) explained this to refer to the words at the beginning of these phrases:
1. בְּרֵאשִׁית בָּרָא (Bereishit 1:1)
2. יְהוּדָה אַתָּה יוֹדוּךָ אַחֶיךָ (Bereishit 49:8)
3. הַבָּאִים אַחֲרֵיהֶם בַּיָּם (Shemot 14:28)
4. שְׁנֵי הַשְּׂעִירִם (Vayikra 16:8)
5. מַה־טֹּבוּ אֹהָלֶיךָ יַעֲקֹב (Bemidbar 24:5)
6. וְאָעִידָה בָּם אֶת־הַשָּׁמַיִם וְאֶת־הָאָרֶץ (Devarim 31:28)
Check out the fourth one, which is from a verse in our parashah! Not all Torah scrolls are the same, and some people think the letter ש (shin) refers to a shin in a different verse. But if you are lucky and you pay attention during the Torah reading, you may see the reader move to the next column during the first aliyah, when reading the word שְׁנֵי (shnei).
Can you imagine how much planning it takes when writing a Sefer Torah to make it come out just right? See if you can find anyone who writes Sifrei Torah and ask them how they do it!