Places to obtain Knowledge about gradle,eclipse,forgeMDK,java and how they work together

Hello everyone, i recently started to learn modding with eclipse using java and forge MDK and it has been quite overwhelming.
Specifically it isnt even about java: i couldnt setup the right configuration for the minecraft client to start from eclipse,  i got error logs like "mods.toml missing in certain file" where the "file" is located in
.gradle --> net.minecraftforge --> "file"
This is where i realized i should probably get a better undestranding about this concepts since i cant answer questions like:
   What is the .gradle file?
   Why is the net.minecraftforge file in the .gradle file, and why does it need the metada file of my mod?
   What is a gradle task?
   What does the runClient gradle task do, and what resources does it need to work properly? Where can i find them?...
Where i arrive at my point, is there a place/book/site where i can obtain a better understanding about this things? To get the bigger picture of what i am really doing. The Forge Documentation doesnt really help that much in this sense.
Thanks!