I know that there is a Terminal package, but it opens the terminal in a new tab, and you can’t really do much in it - it’s bound to bash iirc, and I use zsh on my mac.
Is it possible at all to have terminal the way VSCode has it, at the bottom part of the editor?
The Terminal package should execute your system-default terminal emulator, which should pick your login shell by default. On Mac it defaults to Terminal.app, Linux will pick the TE based on your desktop environment, and Windows defaults to Powershell. However, you can customize this through settings.
Trying to provide a full terminal emulator inside of a text editor is likely to be fraught with edge cases, hence I built the Terminal package so users could have a full-featured terminal, with all the bells and whistles that go along with it. Even things as simple as copy-paste would be funky on Linux. By default text editors use ctrl-C, whereas a Terminal will use that for cancelling a process, and uses ctrl+shift+C by default.
Now, if you are only interested in executing a basic command and showing the output, that shouldn’t be as much of an issue. There are currently a bunch of REPLs available for Sublime that can probably fulfill that feature set. It is once you get into the more advanced Terminal emulator features that things get more complicated, more work to support, and less time spent on the core text editor itself.