2002 Peugeot 206 xsi suspected electrical issue plus other misc issues

Hoping someone can offer advise, please bear with me as i don't even know where to begin on tackling the issues i am experiencing at present.

List of issues below:

Full beam does not stay on
Indicators don’t stay on
Horn works intermittently
Left side headlight out (replaced 2 months ago)
right rear light out
rear VRN light out
shudder under foot when braking
car loses revs when starting up and cuts out
car can cut out and restart whilst moving
water from rear wash but front washers don’t work

I suspect the top 6 are all electrical. How can i identify this to be true and what measures need to be taken to resolve?

The shuddering under foot when breaking i believe is the brake discs?

The loss of power i have no idea on.

I checked to see if there is anything blocking the spray points for the front wash but there doesn't seem to be. Not really sure what else could be causing this?

I am planning a driving trip to Belgium in a couple of weeks time, so i need to resolve this asap. I was planning to get the car fully serviced anyway, but would they also check for any of the above during a service?

Any help here is really appreciated.

R