Hide the Standard New Button from List View #inSalesforce

Steps:

Setup | Object Manager  | theObject | List View Button Layout | Edit the List View by selecting the drop-down next to it. | Uncheck the New[New] from the Standard Buttons list. 

Similarly, other buttons can be added or removed from list view page 

Save and check

Visual: https://www.youtube.com/watch?v=5EpauzF4UDg