Halo 4 almost to end in SR1. need help upgrading

hello. I am a novice gameplayer who purchased a used 360 and got Halo 4. I have played through almost the entire game now with no advancement of rank, upgraded weapons etc, simply because I didn’t understand how to gain those things. I presumed when the game was unlocking “achievements” it was adding up points somewhere. I know this sounds stupid to you experienced Halo gamers, but I’ve literally gotten to the end game of destroying the composer where it’s just getting too difficult to make it through without more firepower, amour, etc. I’ve managed to get there with a straight up SR1 set at Heroic, so I am pretty sure I’m a stone cold Halo player, but I’m officially worn out and don’t want to play anymore because it’s just become too difficult.

the question is this - is there a way to retroactively apply all of my Halo gameplay experience to my character? I simply didn’t realize that as I went along I could have done all of those challenges that are available on the secondary screen. I accidentally pushed the start button twice on the main menu and that’s how I realized I had not been playing properly the entire time and making life much much harder for myself. On the flip side, it made me realize how much better/more focused the experience has probably made me. ha!

in any case, any help would be appreciated, Otherwise I think I’m done - time to move on to another game.

Spartan rank only applies to matchmaking, it doesnt affect the campaign. If its getting too hard invite a buddy over and play co op, its pretty fun with a friend to watch your back

Just play online and you’ll rank up. You can also forge and just sit in a map by yourself if you really want to. Spartan Ops also boosts you up quickly. You get like 2000 exp per game of it.

Rank doesn’t matter as of today I’m rank 76