Translation of Handelsschule

I will send you a summary of the activities from our last vacation last year, but I will be brief, so I will send only the highlights. It is best if we discuss everything, in the beginning of August.
Maybe we would need to say install our dictionary as a software? But I would say instead of install, use our dictionary as a software. So bottom line. If I use the singular form for newsletters and websites, I am on the safe side for both?
Learning a new language is never easy, especially the first foreign language. Unfortunately, it's a bit difficult for me as well. But the vocabulary exercises here are really good.