I want to add new attribute in the add Product as a input filed in admin panel
For creating the attribute you need to follow following steps to Magento 2.2.3:
1) Store -> Attributes -> Product in Magento Admin Panel and Create the attribute which you want to show 2) Store -> Attributes -> Attribute Set add your attributes to the specific attribute set on the use on the product page. 3) Select the attribute set name like "DEFAULT" 4) Drag your unassigned attribute to the Groups section and click Save Attribute Set 5) Flush Cache 6) Do Reindexing 7) Catalog-> Product -> Add Product Find you attribute which you have created then select it.
That's All you need to do.