GCam for newbie

[IO13]

I admit it .. I'm an newbie . I have a Xiaomi Mi A2 Lite already toppled twice due to incorrect operations (I come from a OnePlus One and it was much simpler). I tried to read and reread the many posts you wrote here but I get a lot of confusion because of the many, too much information that there are (double posts, some with the same questions and the answers in contrast to each other). I ask you a humble help .. Having the bootloader unlocked and wanting to install the GCAM which is the easiest guide to follow? Will it allow me to keep OTA updates? I would like to avoid the 3 KO of the phone ..