George Nsd wrote:... From what i searched Java is the language i will be using, i can code in Java so thats cool, i am more worried about which tools i will be using and generally whatever i need to know from the technical aspects of the whole app creation thing.
The Android platform allows you to develop games using both java or kotlin as the programming language. Alternatively, if gaming is your prime interest, then have a look at gaming engines instead. I use Godot and I find it quite good to develop basic games. There's also Unity and Unreal game engines.
George Nsd wrote:Also, i would like to know about your opinions about how likely it is to earn a proper salary by creating apps on your own if you have a few good ideas and creating passive income from them without actually needing to overwork yourself to death just to make a few dollars.
Income should not be the prime focus if you are just beginning with the learning phase. A lot of games posted on the playstore begin without any ads. Once they gain popularity, they start concentrating on income.