Can you use Firefox Fox for an IMAC OS High Sierra Version 10.134

I am considering downloading Firefox Mozilla. I would like to download the Focus version because I hope to obtain some genuine privacy. I find that Apple is worse than any Big Brother we could have imagined. Would the Focus version afford greater privacy? Would it present problems once installed because Apple seems to defeat efforts at privacy even to the point of rendering your computer dysfunctional. I do not have Mozilla right now. I was considering downloading it along with the Focus. What do you think? Does anyone have that combination of Firefox Mozilla with Focus on an IMAC OS High Sierra Version 10.134? Is there any spyware which you can use on Apple MAC, Apple phone, Apple Pro IPad? I had always had PCs until my children of the current millennial generation recommended Apple for my next desktop. Apple itself proclaimed its valuation of privacy. The problem is that neither the millennial generation nor Apple value privacy like my generation does. Your HELP will be much appreciated. LIZ8