could someone help me with my internet problem?

[Nicholas]

I have 2 problems:

1. when im downloading something like a file or game my internet is stable, when im playing a game like call of duty or watching netflix or other video streaming sites my internet speed is slower and it fluctuates a lot, dropping down to less than a kbps and rising back up. I have a program that plots my internet speed on a graph and when im watching videos or gaming it jumps up and down, very unstable.

2. when I run a test on my internet speed on sites like speedtest.net it says I have 5mbps download but when Im doing other things like gaming or video streaming or downloading stuff It never goes higher than 800kbps.
i didnt mean i was runnning a speedtest while watching videos and gaming. i have a program that measures my internet usage, not the maximum im capable of. but i do run speedtests and they are lower than what im using

[Rish]

You should not do a speedtest while you are watching videos.\
second of all, make sure your ISP is not Capping your bandwidth

[Boss]

Call your ISP for help.