Magento 2.3 Click Create New Order then redirect to sales/order_create/index/ - there are header and footer loading
Looking for the help
Try clearing cache.
Clean Cache: php bin/magento cache:clean Flush Cache: php bin/magento cache:flush
(optional) if clearing cache doesn't seem to show any changes, you might need to do a static deploy.
Static Deploy: Note: this will take a bit of time depending on your system.
php bin/magento setup:static-content:deploy
After these processes you can try and reload the page again.
If clearing cache does not help then may be you have added script in a wrong way inside inside the file default_head_blocks.xml.