To estimate the FFO / Net Debt ratio for ENGIE at the end of 2022, we first need to define and calculate the components: Funds From Operations (FFO) and Net Debt.

1. **Funds From Operations (FFO)**:
In the context of credit analysis, FFO is typically defined as the cash generated by the business operations that can be used to service debt. A standard proxy for FFO using the given financial statements is "Profit Loss From Continuing Operations" adjusted for non-cash items (Depreciation, Amortization, and Provisions) and net finance costs. Alternatively, "Cash Flows From Used In Operating Activities Continuing Operations" is a direct measure of the cash generated from continuing operations. 
Looking at the reconciliation provided in the facts:
Cash Flows From Used In Operating Activities Continuing Operations (2022) = 8,488,000,000 EUR.
If we use the traditional income statement proxy:
Profit Loss From Continuing Operations (2022) = -1,793,000,000 EUR
+ Depreciation Amortization And Provisions (2022) = 5,187,000,000 EUR
+ Net Financial Income Loss (2022) = -3,003,000,000 EUR
+ Income Tax Expense Continuing Operations (2022) = -83,000,000 EUR
= 312,000,000 EUR (This is essentially the Current Operating Income adjusted). 
However, for a more comprehensive FFO measure reflecting the actual operational cash generation capacity before working capital changes, analysts often look at the operating cash flow. Another common standard FFO definition (like from S&P) uses the Operating Profit before D&A (EBITDA) minus net financial expenses and current taxes.
Let's calculate a strict EBITDA-based FFO:
Current Operating Income Including Operating Mtm And Share In Net Income Of Equity Method Entities (2022) = 5,367,000,000 EUR
+ D&A (2022) = 5,187,000,000 EUR
- Net Financial Income Loss (2022) = -3,003,000,000 EUR
- Income Taxes Paid (2022) = 1,504,000,000 EUR
FFO = 5,367,000,000 + 5,187,000,000 - 3,003,000,000 - 1,504,000,000 = 6,047,000,000 EUR.

2. **Net Debt**:
Net Debt is calculated as Total Financial Debt minus Cash and Cash Equivalents.
Total Financial Debt typically includes Long-term Borrowings and Current Borrowings.
Longterm Borrowings (end of 2022) = 28,083,000,000 EUR
Current Borrowings And Current Portion Of Noncurrent Borrowings (end of 2022) = 12,508,000,000 EUR
Total Financial Debt = 28,083,000,000 + 12,508,000,000 = 40,591,000,000 EUR.
Cash And Cash Equivalents (end of 2022) = 15,570,000,000 EUR.
Net Debt = 40,591,000,000 - 15,570,000,000 = 25,021,000,000 EUR.
*(Note: Derivative financial assets and liabilities are typically excluded from Net Debt in standard ratios unless specifically defined otherwise, as they are operational hedges or marked-to-market values, not debt instruments).*

3. **FFO / Net Debt Ratio**:
Using the calculated FFO of 6,047,000,000 EUR and Net Debt of 25,021,000,000 EUR.
Ratio = 6,047,000,000 / 25,021,000,000 ≈ 0.2417 (or 24.17%).

If we instead use the "Cash Flows From Used In Operating Activities Continuing Operations" (8,488,000,000 EUR) as a proxy for FFO:
Ratio = 8,488,000,000 / 25,021,000,000 ≈ 0.339 (or 33.9%). 

Given the most standard corporate finance definition for FFO (Operating Income + D&A - Net Finance Costs - Taxes), the value yields ~24.2%. Let's proceed with 24.17%.

<answer>0.2417</answer>