There is a option to make columns uneditable but how to make row uneditable?
You can create a Slice as “read only” if you need an entire part of the application uneditable.
All rows of the table, or just some rows?
I was assuming you could make rows uneditable from the Tables tab in the “Are edits allowed” field by making an IFS() expression based on if a column in that row had a specific value but when I save the edits Appsheet tells me it cannot find the column.
Your assumption was wrong. That setting affects the entire Table, and cannot use values from individual records within the Table.