insert - object - formula

insert - object - formula
I closed the table with ready formulas how to turn it back on

Whats the “table”? How did you manage to “close” a table, what’s the “it”?
Please edit your question to explain your issue more precisely and to attach an example demonstrating it.

And as usual mention OS name and LO version

In which format the file was saved?

In the formula editor, click View > Elements to toggle visibility.