To explain in detail:
MB/s means "Megabytes per second".
Mbps means " megabits per second".
Speedtest shows it in two types: MB/s or mbps depending upon settings. If it shows mbps, then you have to divide by 8 to get the actual speed in Megabytes. This is the actual speed shown in IDM, UC Browser, torrents, etc.
So, 8mbps = 1 MB/s. Or to simplify, it would take 1 second to download a 1 MB file with a 8 mbps or 1 MB/s speed.
Hence, to compare Sadiq bro and Vicky bro's speeds, let's get them to same type. Vicky bro's is in MB/s whereas Sadiq bro's is in mbps. Let's convert both of them to MB/s.
Vicky bro = 8 MB/s. Screenshot posted above.
Sadiq Bro = 40 Mbps = 5 MB/s.