hard drive - Attempt to fix macOS startup Volume after dual-boot Linux partition removal

I have attempted to install Linux on my MacBook Pro 15″ alongside macOS (Catalina) for a team project.
Since I needed the space reserved for the Linux partition back, I have decided to remove it through the standard disk utility.App procedure.

As you can see from the sidebar view, the two partitions reserved for Linux were respectively:

disk0s3: for swap memory (16 GB), formatted as MS-DOS FAT
disk0s4: (350 GB) Volume for the OS

There’s also an SD card, but it is used as an external support

Firstly, I foolishly removed (with -) the SWAP partition (disk0s3 volume); Then I noticed that also disk0s4 was not a Container disk1 “child” anymore.

To better understand what was going on, I run diskutil list, whose output was

Then the laptop suddenly died (I guess the battery was low).

Currently, As I turn it on, it just displays the grub2 menu.
Also, By restarting it and by keeping pressed alt, I can only choose “EFI boot” and by pressing enter, it returns back to the initial stage (grub2 menu).

Therefore, I made the laptop go into recovery mode through alt+cmd+r.

By running the terminal command diskutil no volumes are currently listed under disk0, neither under disk1 (Differently from what happened in this case) as it seeems it does not recognise the SSD anymore (which, btw is a Samsung SSD 970 Evo Plus, size 1 TB).

Is there any way to solve this trouble and start back macOS?

If it would help, Here below you can find the output of gpt -r show disk0