Hey @Pastor-David-R, just wanted to say, really cool to hear you are looking at running UT in place of android! Im similar, as im a lover of linux generally and use linux desktop OSs for work and life on my home systems. About 5 years ago i felt the same as you have said now and had similar questions to what you asking.
I just wanted to say that i have been very happily using and loving UT as my daily phone OS since 5 years ago and similar to you, while i have always been 'techy', i did not know much about phone stuff back then but now im here it actaully is really easy to get a phone setup with UT, once you've picked one that suits you from the supported devices @arubislander linked.
Just to put my bit out, like @Keneda said, fairphone are really cool but for me were too pricey (from my experience), so i just wanted to suggest Oneplus Nord N10 also, as it is a pretty good phone, you can find them fairly cheap (from my experience) and they run UT really stable (also from my experience).
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