excel with the issue of counting function

AB
1 0
2 2
3 3
4 9
5 6
6 3
7 5
8 3
9 8
10 5

table above, (1) how to seek B1:B10 in the numerical equivalent of 2 cell number?
(2) how to seek B1:B10 in the value equal to 2,5, 8, the cell number?

Insert function COUNTIF COUNTIF (B1:B10, 2)
COUNTIF (B1:B10, 2) + COUNTIF (B1:B10, 5) + COUNTIF (B1:B10, 8) 1 .= COUNTIF ($ A $ 1:$ B $ 10,2)

2 .
= COUNTIF ($ A $ 1:$ B $ 10,2) + COUNTIF ($ A $ 1:$ B $ 10,5) + COUNTIF ($ A $ 1:$ B $ 10,8) 1.= COUNTIF (B1:B10, 2)

2.= SUM (COUNTIF (B1:B10, (2,5,8)))