Unable to boot Mac OS and disk utility unable to repair disk after bootcamp delete win10
You were close. The correct commands are given below.
gpt remove -i 2 disk0
gpt -f add -i 2 -b 76806 -s 122061322 -t apfs disk0

The question you gave as a link had a drive with a 512 byte sector size. Your drive has a 4096 byte sector size. The means your APFS container partition starts at sector 76806 instead of the value you choose of 409640. You can see this in the image you posted in step 8. Here you posted the output from the command gpt -v -r show /dev/disk0. In a typical macOS installation, there would be no free space between the two partitions.
Generally, running any application or command from a older version of macOS to repair a drive containing a newer version of macOS is not a good idea. On my 2018 Mac mini, I have Mojave and Big Sur installed in the same APFS container. When I run diskutil verifyVolume disk0s2 using Mojave and again using Big Sur, I get different results. Mojave incorrectly finds errors and Big Sur does not.  Using Mojave to try repairing an APFS container with Big Sur installed could more damage than good. In your case, I do not know if any of your attempts at repair damaged the contents of the drive.