If you don't want certain Items to show for your online ordering, you can simply hide them in YourMenu so they do not display! You can also hide Items from showing in your POS, but still show them online.
To hide/un-hide a Category:
On the YourMenu dashboard, go to Menu > Categories and locate the Category you wish to edit
Click the Edit button next to the Category
On the top of the edit screen, change the Hide toggle to on or off
Click Save
To hide/unhide multiple Categories at once, you can click Quick Edit on top right of the screen. Once done, click Save!