here we are!
I managed to enter in recovery mode.
The only way to recover my data seems to be this procedure:
but I need to install busybox.
Since I can work only in recovery mode, could I install it via recovery?
The alternative is to install a rom with root and busybox, but I can't put the device in sideload mode, I don't know why...
Once I'm in recovery mode, I push twive vol down, and it should be the "install zip from sideload", but the adb status remains recovery...
I don't know why.. It's very frustrating..