Hiw do we dual boot on M.2?

How do we dual boot using Mageia 8 and another OS (like Ubuntu, another Linux version or, yes, even W10) on the M.2 NVME PCIe4 x4?

Would it be better to dual boot using the other HDDs or would loading separately and use BIOS to change when needed?

Thank you.

Asus ROG Strix B550-F MB
Asus TUF RTX 3060 OC Edition 12GB GPU
AMD 7 3800x CPU
32 GB 3200 DDR4 Memory
EVGA G5 850 Watt PSU
2 Seagate HDD 2TB each
Seagate 2280 NVME M.2 PCIe4 Gen 4 - 500 GB
DVD burner
Card Reader