Then that has nothing to do with going online. Which confuses me even more. To update your system, you can just use ChoiDujourNX. Grab the firmware files for the firmware you want to update to (9.0.1 is the latest). Linking to these files isn't allowed here, but to can use Google to find them. However, you will need to update your cfw before you do this! There are guides for this. Assuming you're using regular atmosphere, you would download and extract the latest release from
https://github.com/Atmosphere-NX/Atmosphere/releases , as well as the zip file from the first post in the thread
https://gbatemp.net/threads/i-heard-that-you-guys-need-some-sweet-patches-for-atmosphere.521164/ . Once those steps are done, you can download ChoiNX
https://files.sshnuke.net/ChoiDujourNXv102.zip to your switch. Put the firmware files in a folder on the root of your sd card. Not the zip, but the extracted zip. Remember I can't link the firmware files.
Inject. Launch Homebrew menu by holding R and launching any game. Hold R until you see the Homebrew menu. Launch and update through ChoiDujourNX. If you're using autorcm, remember to select it. If you don't know, if you need to slide a jig into the switch's right controller port, then you don't have autorcm. If you just plug your injector into the usb and that's it, then you have autorcm and make sure it's checked while updating. Restart console.
I'm not sure how your injector works and if you boot hekate first or just atmosphere. I'm sure you will need to update the payload on the injector. If you don't use hekate, good, because I assumed you didn't in this guide. You would need to update your injector's payload file with the latest fusee-primary.bin from the download section for atmosphere. You must do this.
If you want to go online with your switch and play legitimately purchased games, you could set up emunand and do that. There are guides and it's much more complicated.