Bitrate and fps can be affected by how good of a processor your computer has and your internet upload speeds.
As mentioned before check your output settings in OBS and make sure you have an appropriate bitrate for your stream quality. This is a handy starting guide for bitrate
https://stream.twitch.tv/encoding/ you don't want to put in too low of a bitrate but you also don't want to put in something too high that will make your stream wonky.
I'd highly suggest getting a cat 7 ethernet cable to stabilize your internet connection. I work on SM and cannot get the quality I need over wifi even if the modem/router is in the same room. When I cam I turn off as many wifi devices as possible in my house. That may be a bit overkill since I have the 2nd best package my ISP offers, but at least make sure something like another computer isn't uploading videos or something.
Check your upload speeds, lots of ISP advertise "great" internet but in reality it's only great download speeds. Your bitrate should really only be 50% of your available upload bandwidth, so if you're only getting 5Mbs upload you don't want a bitrate of 5000.
For your processor, close all unnecessary applications and windows on your computer. Open up your task manager to see what may be running in the background as well, you might be surprised to find some bloatware eating up your CPU. Also, close all unnecessary tabs in your browser. Try not to stream music to save internet bandwidth, but if you must, use another device to do it. Having something like YouTube or Spotify open on your computer can eat up a lot of CPU. Also, I know I had a lot of issues with browser add-ons eating CPU so check your browser task manager as well.
A good processor is an often overlooked factor in camming, upgrading to a great processor was a game changer for me and made life so much easier, you can get by with a crappy processor but it means you can't do 1080p and is in general a headache. For years I cammed on a half dead CrackBook Pro with a 3rd gen processor and managed to get a good stream at 720p using these methods, so it's possible, but unless you already have a top of the line processor "good processor" should be up there on your shopping lists.
Overall remember that a smooth stream in 720p at 30 fps with a 2500 bitrate is better than a choppy 1080p 60 fps stream, so don't overwork your computer and internet just because 1080p sounds nice.