Problem after software update and reboot

It is quite possible that Secure boot is what led to the problem with Zorin. I cannot say that with certainty. But if Secure Boot was enabled during an update, this could cause corruption. I would highly recommend disabling Secure Boot as your first step.

At times, code that you know is safe, and comes from a reliable source, might not have a digital signature in the Secure Boot database.
For example, you can download numerous Linux distributions directly from their developer site, even verifying the distribution checksum to check for tampering. But even with that confirmation, Secure Boot will still reject some operating systems and other types of code (such as drivers and hardware).

If you are running only Linux, I can see no need at all to re-enable secure boot later.

I am not sure what you mean by "not sure which option to select" as I cannot see your screen or what options you are presented with.
Are you able to take a photo?

Okay. That makes sense.

It's the same photo i posted last. I haven't selected anything yet.

That screen from the photo you posted last- you would need to back out of that settings dialog and enter the one advised by the link above to access the Security Tab or Advanced Options in EFI settings.

BIOS setup at your boot choice screen will take you into the BIOS settings. You will most likely have to enable advanced options to access the secure boot under either the boot order tab or security tab. While you are in there make sure fast boot is also disabled. Pressing F10 will save your configuration and exit with a prompt that you are sure, select yes. Then you can attempt to boot Zorin again, but you will most likely need to fix a few things as Aravisian pointed out.

I think i disabled Secure Boot.

It rebooted, and there was some trouble getting to Try Zorin (i wasn't able to get a picture of the screen though). I opened the Terminal (and had some issues 'cause i misread the commands) and now I'm here.