As someone who had little parrot experience but did a lot of research before adopting her amazon...
Definitely meet the bird before you make any decisions. Don't expect the bird to act in a certain way or look for an immediate bond. Do find out as much as possible about his/her history including previous owners, any socialization/breeding in the bird's past, diet, enrichment opportunities, behavioral quirks and issues, health issues; anything your friend might know. Even if you learn nothing about the parrot's past, however, that doesn't mean you will struggle - it can just be nice to have an idea of their experiences as a starting point. Also be honest with yourself about whether the volume, personality and potential bite of an amazon is right for you and for your household if you live with others.
Personally, I still use gloves with my amazon. That said, we have come a long way and I can almost always get her to step up and accept pets. She often plays with my hand and rarely bites me although she has not yet learned to control her play beaking and would ocassionally do some damage with no gloves on. The gloves were a personal decision as she had no fear of them and I would have been bleeding badly in the beginning without them as she can change her mood on a dime. They allow me to handle her safely even in the worst of moods whereas gloveless if she decided to run up my arm towards my face I could be in a dangerous position. I'm working to train bite inhibition but I do not want to take away her playfulness with hands as it is definitely helping us bond and one of our daily routines. Living with my amazon - who is an ex breeder yellow nape hen from a home that gave her pecans as a sole diet for years and deliberately exposed her to drugs - is a lot different than the cockatoos, macaws. conures and others I have met or read people's experiences with. She is not a bird I can fully trust whereas my GCC and starling are well behaved on shoulders and near faces. She also has a clear overload point where you NEED to set her down and let her calm down or you will be bitten from excitement. I get displacement bites from her. She's a wonderful bird, don't get me wrong, but I think a lot of people would struggle with her "bipolar" attitude. I know I am glad I have Eva too who is the complete opposite.
That said, my amazon is more on the extreme side in terms of behavior. Many amazons can be trusted on arms and shoulders and not all of them exhibit "amazon overload". And even for her, over time she is becoming more calm, more playful and much less aggressive as she settles into her routine and learns to trust us. Again, that's just my experience and probably on the more extreme end behaviorally. Just be honest about what you want in a parrot and you will be fine.