Referencing a column based on values in another column

Hi, I'm trying to tell which column I want to look in table b based on values in a column in table a. The column in table A have 1, 2, 3, 4 in them and table B have columns named 1, 2, 3, 4

In excel id use something like index/match but i can't wrap my head around what to do in DAX.

Below you can see what I'm kinda trying to do.

Column =

var _var1 = 'Table_A'[Column_1]

var _var2 = "'Table_B'[" & _var1 & "]"

RELATED(_var2)

Hope someone has some good input. Thanks in advance!