Hi there!
How do I hide the false cell before complete. This is formula.
=VLOOKUP(A8.{“z”"#N/A";“Paris”“France”;“London”“UK”;“Buenos Aires”“Argentina”;“Lisbon”“Portugal”;“other_place”“other_country”}.2.0)

Thank you!

“How do I hide the false cell before complete.” I don’t understand. What is a “false cell”? What do you mean by “before complete”?
Did you ever succeed using a point (full stop) in place of the parameter delimiter? You shouldn’t. Replace the points with semicolons.
What are the backslashes supposed to mean? What are your settings under Tools>Options>LibreOffice Calc>Form ulae>Separators?

It’s your responsibility to ask clear questions.
See Guidelines for asking e.g.

Don’t try to use inline arrays in place of lookup tables. That’s very limited and inefficient.
If you use inline tables at all, you need to use the correct separators.
The separator behind Array column: must be used beween the columns of any row.
The separator behind Array row: ends one rtow and starts the next one.