I have found information about "toggle editing" but I don't have the option in 10.4. Another suggestion was to create a template but everything in "editing windows" is also greyed out.
This is what my toolbar looks like:
Do you have a vector layer selected in the table of contents?
Did you click on the toggle arrow beside 'Editing' and begin editing?
The template reference is to chose whether you are editing a point, polyline or polygon using one of your layers as a template or a generic template.
When you add a layer to ArcMap and start editing, that is how the toolbar looks. However, once you select the Layer under "Create Features", the rest of the options become available for you to use:
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