New line after going into folder terminal

If you look at your .zshrc, you will see a line prompt adam1 which defines how your prompt is composed.

The definition of the adam1 is in the /usr/share/zsh/functions/Prompts/prompt_adam1_setup. A look at this file confirms it is rather complex : it measures the prompt length and compare to 40. If the prompt is too large, a newline is inserted before the %.

The command prompt -l displays the alternative themes. Then you can pick one of them and type for example prompt fire. When you are happy with an alternative, you can edit the .zshrc and change your future default theme. redhat and suse are some examples of single line prompts.