Tips from the pros

[Baeztoberfest]

So I had a few questions about matchmaking.

 

I used to be good at halo 3 and halo reach and understandably it's a completely different game but my K/D is barely 1.05. What am I doing wrong?

 

And by that I mean can some of the seasoned players shed some light on how to be a better player?

 

Also forerunner weapons. Can anyone explain their pros and cons? I know human weapons are crap for shields but excellent for health damage. And visa versa for covenant weapons. How do forerunner weapons for into that equation? Thanks.

 

Any tips are worth it to myself or any new player wanting to learn. Thanks for your time and patience and I hope this leads to better matches in the future.