If header then - pick below row cell

Please post a sample sheet ( no pics) - Much easier to work with

try
=INDEX(Sheet2!$A$3:$C$5,,MATCH(D$1,Sheet2!$A$2:$C$2,0))
where
Sheet1, C1: EXAMPLE1, D1: EXAMPLE2, E1: EXAMPLE3

put it to Sheet1 A3, drag right and down

lookup array cannot be source of lookup value
=INDEX(Sheet2!$A$3:$C$5,,MATCH(Sheet2!B$2,Sheet2!$A2:$C2,0))
see? everywhere you have Sheet2!... but where is sheet1 ?

from my post above:
=INDEX(Sheet2!$A$3:$C$5,,MATCH(D$1,Sheet2!$A$2:$C$2,0))
and formula is inputed into Sheet1, so I don't have to use sheet1!D$1 because D$1 is in default sheet for formula.

Definition:
MATCH(lookup_value, lookup_array, [match_type])

The MATCH function syntax has the following arguments:

## lookup_value Required. The value that you want to match in lookup_array. For example, when you look up someone's number in a telephone book, you are using the person's name as the lookup value, but the telephone number is the value you want.
The lookup_value argument can be a value (number, text, or logical value) or a cell reference to a number, text, or logical value.

## lookup_array Required. The range of cells being searched.

## match_type Optional. The number -1, 0, or 1. The match_type argument specifies how Excel matches lookup_value with values in lookup_array. The default value for this argument is 1.

EDIT:
You need to define source of lookup value(s). Can be Sheet3, can be any other row everywhere but not in lookup array. You can define lookup value manually of course but it will block dragging formula to the left or right. If you have lookup array horizontally will be easier to have the same vector with source of lookup value.