no selection in terminal preferences

Confirm you’re running 3.4.15, open a few new sessions (Shell > New Window, or Shell > New Tab), switch to English and see if there’s something odd with the Swedish localization, then check with the app developer’s support forums.

First iTerm2 is its own application, and does not do anything based on your macOS Terminal preferences. I've been using iTerm and iTerm2 since the early 2000's when Mac OS X 10.1 was originally released (I did have 10.0, but it was just experimental).

As MrHoffman says, you want to look at the macOS Terminal menu entries for things like tab and sessions.

With respect to iTerm2, this is what its preferences look like:

and you will also find things like tabs and sessions in the iTerm2 menu entries.

If you are going to spend a lot of time in iTerm2, then it would be good to first skim through the iTerm2 documentation

https://iterm2.com/documentation.html

or if you like not having to click around

https://iterm2.com/documentation-one-page.html

You may find useful information not in the regular documentation in the FAQ, as I know I have

https://iterm2.com/faq.html

And there is the iTerm2 Features

https://iterm2.com/features.html

I like to say, iTerm2 is Open Source, and as such it includes the Kitchen Sink 🤪

My job has me living in a terminal emulator, and I've read the iTerm2 documentation several times, and I still do not use a quarter of all the features available.

I have also been through the macOS Terminal usage a lot, and I have to tell you that there is a lot of hidden value in macOS Terminal. However, whenever I read a Mac book that mentions macOS Terminal or find an online webpage on macOS Terminal, they spend 5 seconds on the preferences, most of which is focusing on the different color schemes, and then they dive into using the Unix commands.

If you want a primer on using commands, then start with

macOS Command Line Primer

or get a book on Unix command, and Google various macOS only commands.

But finding useful information about macOS Terminal itself and its features is difficult. At work, I have a Confluence page on macOS Terminal that talks about its features, and nothing about using the Unix commands (except for ssh, which most users need to access company Linux systems). Unfortunately, it is full of company proprietary information, so I cannot make it available to the general public.

But many of the core features you find in iTerm2 exist in macOS Terminal, it is just difficult to find out how to use them.

Is the script marked executable, not quarantined, and owned by your login?

Please post the output of the following two commands.

id
ls -ale@ ~/.zshrc

You’ve repeatedly referenced .zhsrc here too, while the necessary filename is .zshrc. (On Unix systems, “rc” files are typically configuration and customization scripts.)

Two other discussions to read about the zsh script files, one more specific to macOS and one somewhat more general:

https://apple.stackexchange.com/a/388623

https://unix.stackexchange.com/questions/71253/what-should-shouldnt-go-in-zshenv-zshrc-zlogin-zprofile-zlogout

As you are unfamiliar with shell operations, I’d STRONGLY suggest using a different login for your experimentation. That’s easier to reset and reload, should something go wrong.

Again, it’s .zshrc, not .zhsrc.

Add that to the .zshenv environment-variable file, restart iTerm, and try again.

Bob: Surprised that those scripts don’t need to be executable. That seems rather more like a latent bug. But maybe that expectation is from spending time on an OS that tends crankier about file protection correctness. Learn something new.

The iTerm2 version is found like most macOS apps. You go to the menu bar, click on the app name, and select "About iTerm2"

The most recent version of iTerm2 is

zsh is part of current macOS. You’ll not need to add that shell.

If you’re on a recent version of MacOS, there are a couple of ways to switch shells from the older defaults (the default shell has changed three? times), including from the command line, and your login can also select the shell using System Preferences > Users & Groups > control-click to select your user Advanced Options.

Permission Denied is usually that the iTerm app hasn’t been granted partial or full device access in System Preferences > Security & Privacy. But (depending on the details of the error) it can also be that the scripts aren’t marked as executable (chmod +x), or aren’t configured with ownership and protections associated with your login (chmod, chown, ls -ale@)

With respect to shell changes. The first Mac OS X 10.0 defaulted to the csh shell. Then around 10.3 it switch to bash as the default, and with Catalina 10.15 it defaulted to zsh (for GPLv3 licensing reasons; namely Apple could not update to a newer version of bash).

As for zsh, I am still a bash user, mostly because when I'm spending so much time in iTerm2, I'm actually ssh'ed into Linux, Solaris and AIX operating systems where I'm using bash. It makes my life easier if all my shell initialization scripts, appearance and keyboard behavior is the same on all platforms.

So I do not know anything about zsh specifics. Sorry.