You can add references to your EndNote Library by logging in to OneSearch. Search for 'Intrinsic motivation'.
On the results page, click on the Cite icons 
to generate the citation.
Click on Export RIS option followed by Download button. The selected citation is downloaded in RIS format. This format is compatible with EndNote.
The RIS file will automatically open in EndNote. If not, locate and open the file from your Downloads folder:
If you are prompted to choose an Import Filter. Search for RIS and select RefMan RIS
The selected reference should be added to EndNote.
In PubMed, select the articles you'd like to add to your EndNote Library, then click on the Send To link on the top right of the results page as in the image below. Select the option for Citation manager and Create File.
You can open the downloaded file (.nbib) with the EndNote program or you can Import the file into EndNote.
In EndNote, go to File > Import > File. Select the downloaded file of citations and ensure your import filter is changed to PubMed (NLM).
Conduct a search using Google Scholar and click on the double quotation marks that you wish to import into your EndNote Library.
Click on the EndNote link.
If the .ENW file does not automatically open in EndNote, double-click the file from your Downloads folder. The reference should automatically open in your EndNote Library.
You can create a reference manually by clicking References followed by New Reference.
For each reference record, you can attach up to 45 items (such as images etc.) with no size limit. Choose the + Attach PDF button to link a PDF or any file to the reference.
You can also edit a reference manually by simply double clicking on the reference that you would like to edit.
While there are many fields, you only need to populate the fields that are essential to the citation. Once done, you may click Save or click the small cross on the top right corner of the screen to close the editor and save your changes.