macOS Catalina默认的shell使用zsh，个人用户的环境变量文件路径是，当前用户主目录下的.zshrc文件。以下是本人的.zshrc文件的内容，可以作为参考：

export PATH="$PATH:/Users/liangtianyu/work/flutter/bin"
export PATH="$PATH:/Users/liangtianyu/work/istio-1.4.5/bin"
export PATH="/usr/local/opt/mysql-client/bin:$PATH"
# added by Anaconda3 2019.07 installer
# >>> conda init >>>
# !! Contents within this block are managed by 'conda init' !!
__conda_setup="$(CONDA_REPORT_ERRORS=false '/Users/liangtianyu/anaconda3/bin/conda' shell.bash hook 2> /dev/null)"
if [ $? -eq 0 ]; then
    \eval "$__conda_setup"
else
    if [ -f "/Users/liangtianyu/anaconda3/etc/profile.d/conda.sh" ]; then
        . "/Users/liangtianyu/anaconda3/etc/profile.d/conda.sh"
        CONDA_CHANGEPS1=false conda activate base
    else
        \export PATH="/Users/liangtianyu/anaconda3/bin:$PATH"
    fi
fi
unset __conda_setup