im getting a bit confused now lol
The Switch has mechanisms in place to prevent downgrades. If you were on a higher system version and downgraded, your system version might not match your efuse count (generally, fuses get irreparably burnt when you update your system and boot normally). If this is what happened, you can't boot your system normally. You can check your fuse count using Hekate, and you can check if the fuse count comports with your current system version.
If you're using an emuMMC, then a problem with your sysMMC may be preventing your system from booting your sysMMC normally.
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is 11.0.0 best firmware to keep on at this time
If you are using SX OS, then yes, 11.0.0 is the best system version to use, and you will probably never be able to update. This means some newer games probably won't be compatible with your system in the future.
If you aren't using SX OS, then you can update to 12.1.0.