I don't know my CO2 emissions what should I fill in

To be determined, with scope 1 and 2 as first step

If a measurement is missing, "to be determined" is the correct answer, not an estimated figure and not a blank field. The VSME basic module of EFRAG requests emissions broken down by scope 1, 2 and 3, according to the GHG Protocol classification. If these figures are not available, filling in with an estimate without substantiation is riskier than indicating that the measurement still needs to be done: a made-up figure will be taken over by the customer and will reappear next year as a comparative figure.

The practical sequence is: start with scope 1 and 2, as these can usually be reconstructed within a few weeks using invoices for gas, fuel and electricity. What is the direct greenhouse gas emission (scope 1)? and What is the indirect emission from purchased energy (scope 2)? show which sources are sufficient for this. Scope 3 is the component that hardly anyone has measured in the first measurement, because it concerns the chain of suppliers and transport; here too it applies that "to be determined" is acceptable as long as you update the file afterwards once a calculation is available. If you receive multiple customer inquiries at the same time about the same emissions, you will find the complete breakdown in customer asks about scope 1 2 and 3 emissions, how do I fill that in correctly.

Why an estimate is not sufficient here

The VSME basic module of EFRAG is set up as a fixed set of indicators with a unique unit per scope; an estimate without a calculation method does not comply with this classification and produces a figure in the next completion round that cannot be traced back. The GHG Protocol provides the methodology by which scope 1 and 2 can be substantiated from existing invoices, which justifies "to be determined" for scope 3 until that calculation is made.