Apple version for Mobile download of Firefox

I went on Apple app store and there are many Firefox downloads from which to choose. I have an iphone 15 Max Pro and the version the internet said to choose isn't among those on Apple's app. You've sent me links and don't seem accessible, at least for me. My iphone is currently Safari/Bing. Mac is Firefox/Bing. Thanks much, Avril Levinsohn [email removed]@nyc.rr.com