linking tabs on a spreadsheet anticipating adding lines and adding missing data

What you are asking for is very common(at least in this forum).

The way most Excel databases work is;
1. On a sheet, you collect and manage records. These should be very inclusive(all related info on one line for each record.
2. Some columns and cell get calculated using worksheet functions.
3. The autofilter helps a great deal in filtering these records. It's a great tool.
4. Macros are used to do things like make reports. Like deadline reports.