Complete noob here with some questions

Hello! Please be nice I'm really dumb and new to this.

I'm having trouble with a very leaky tap that's unable to be turned off. I've watched some videos and I'm getting a new adaptor, wrench, washers, hydroseal valves, thread seals and a reseating tool tomorrow... but I have some questions as to the feasibility of me fixing this...

  1. Will a wrench even be able to unscrew where the orange arrow is pointing? It looks kind of cemented on...

  2. What is the red arrow even pointing to? Do I have two adaptors with one cemented on? Or is this an adaptor for the tap because it didn't have any screwy insert sockets? Why would a second hose adaptor even be needed then? What even is this? Can I unscrew it and take it off? Should I just leave it alone? Some of the water looks like it leaks from there too.

  3. If I need to replace the whole tap, how would I even do that? Do I need a tap with a vertical entrance like that to screw onto the pipe? How was that even done in the first place since the wall is in the way...?

Thank you very much and sorry if these are stupid questions.

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