To estimate the FFO/Net debt ratio for ENGIE for 2022 using S&P’s methodology we:

1. **Identify Funds From Operations (FFO)** – S&P defines FFO as net cash from operating activities after interest expense and before capital expenditures.  
   - Net cash from operating activities (CFO) is given as **€8,586 million**.  
   - Interest paid (classified as financing) is **€822 million** – this is added because CFO excludes financing costs.  
   - Therefore, **FFO = CFO + Interest paid = 8,586 + 822 = €9,408 million**.

2. **Determine Net Debt** – Net debt is total debt minus cash and cash equivalents.  
   - Total borrowings = Long‑term borrowings (€28,083 million) + Current borrowings (€12,508 million) = **€40,591 million**.  
   - Cash and cash equivalents = **€15,570 million**.  
   - **Net debt = 40,591 – 15,570 = €25,021 million**.

3. **Compute the ratio**  
   - **FFO / Net debt = 9,408 / 25,021 ≈ 0.376**.

Thus, the estimated FFO/Net debt ratio for 2022 is **0.376** (or about 37.6%).

<answer>0.376</answer>