Hi Marie-Sue

just my opinion but I'd say 'yes'

from what I've learned so far your niche is the subcategory of the broader market you want to specialise in.

In the starter training Kyle gave an example of basket ball as the broad market and 'basket ball drills' as a subcategory or niche of that.

When you've decided on your niche and got to the point of deciding on products to promote you you can have more than one - you just want them to fit within the niche and be of use to your target audience.

So if Amazon and Nike provide affiliate programs for a product that fits your niche you create content to support and include them.

Your niche can be pretty much whatever you want but you should validate it by checking the level of interest in it so you know there is traffic.

Kyle goes through how to do this in depth in the beginner course but you can use tools like Google Trends and the keyword tool here at WA to get an idea.

I've not long started here myself so this only my opinion and happy to stand corrected by those more knowledgeable here.

I definitely think going through the first module or two of the Online Entrepreneur Certification couple times will answer your questions in full though.

Hope that helped some and best of luck :)