laravel db not found

export PATH=~/.config/composer/vendor/bin:$PATH

source ~/.bashrc

use Illuminate\Support\Facades\DB

#these commands executed on Ubunyu 20.04
export PATH=~/.config/composer/vendor/bin:$PATH
source ~/.bashrc

echo 'export PATH="~/.config/composer/vendor/bin"' >> ~/.bashrc
# or
echo 'export PATH="~/.config/composer/vendor/bin"' >> ~/.zshrc

use Illuminate\Support\Facades\DB;