I see that the Bernina 765 is a special edition which is no longer available. On the Bernina website it said when I looked up manuals, it said to refer to the regular Bernina but there was not a 760 so I am not sure if it closer to a 770? Anyway, have you looked at your manual for the embroidery section? I know there is a lot of editing that can be done on screen from the software that is in my Bernina 590. Also, there is a free basic embroidery program on the Bernina website you can download but I can't remember if combining designs is in that program. There is also a downloadable free embroidery workbook that is located under the Learn & Create tab on the Bernina website. If you have a dealer who is knowledgeable about embroidery it would be worth a call. There is also a lot of YouTube Bernina videos on different topics. Title of the workbook is: (sorry about the big font, I couldn't figure out how to make it smaller)
"My BERNINA Embroidery Machines Mastery Workbook"