Marrakech is a beautiful and very interesting city. I suspect that in July it will be quite hot.
What exactly do you want to know? What are your interests? Budget?
One thought I had was that you might look at TripAdvisor. There are many single and multi-day tours listed and rated. I can’t imagine you wouldn’t find something to meet your desires.
On a cautionary note, my husband and I recently returned from a tour of Morocco. I remember thinking, more than once, that I was glad we hadn’t tried it on our own. We are very experienced at independent travel and even have some ability to speak and understand French. Nonetheless, I was very glad to have a professional, native Arabic speaker in charge. To be clear, I am not thinking of safety issues, so much as logistics, and efficient use of time.