regarding your first question, you can use VLOOKUP function to accomplish this task.
see the link below for understanding and using VLOOKUP function.

http://www.contextures.com/xlFunctions02.html

however if need more assistance regarding implementation of VLOOKUP, attach here a sample file.

regarding your second question, you need to put more info about what you want to Find and Replace with (mention your criteria).

Regards.

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starguy
PAKISTAN
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