OR LastName = "input"

Other than that, it looks good, although you may get an error if input is a non-numeric value. What error are you getting?

this is the 'and' clause of my query. the and clause works fine but they will be ignored when i add in the or clause.

AND Address.AddID = PersonDetails.AddID AND PersonDetails.Status = 'active'

the database seems to ignore my 'and' clause at the back.

WHERE OID = input OR FirstName = 'input' OR LastName = "input"

they will be ignored when i add in the or clause.

Consider this simplified example:
SELECT *
FROM MyTable
WHERE Field1=1 OR Field1=2 OR field1=3

If a row has a value of 2 for Field1 and 2 for Field2, the following will happen-
DB checks Field1=1 (false)
DB checks if Field1=2 (true)
DB doesn't need to check if Field1=3 because the statement is already true.
DB displays the row.

Now let's look at the following statement:
WHERE Field1=1 OR Field1=2 OR field1=3 AND Field2=1
DB checks Field1=1 (false)
DB checks if Field1=2 (true)
DB doesn't need to check if Field1=3 (or Field2=1) because the statement is already true.
DB displays the row.

What you need to do is add parenthesis. For the example, you probably want:
WHERE (Field1=1 OR Field1=2 OR field1=3) AND Field2=1
In this case:
DB checks Field1=1 (false)
DB checks if Field1=2 (true)
(DB doesn't need to check if Field1=3 because the parenthetical statement is already true.)
DB checks if Field2=1 (false)
DB does not display the row.

will the db check records field1=1 is true and proceed to check records field2=1 & check records field3=1
& these records will be compare with my AND Clause which compares the primary key of other table & display these records?

I know that this seems a little complicated but if this is possible, it would be great.

I have managed to solve the error by placing my and clause at the front. Thanks alot for the help.