Right I'm a complete novice at this stuff. My brother has given me a active subwoofer (Fusion EN-At110) and now I'm going to get a Double Din JVC KW-AV60BT and 4 Pioneer TS-A6813I speakers. Want cables will I need to plug to subwoofer to the unit/battery. Also want the stalk adapters to work so want ISO plug do I need. If possible can you get the original mic from the Fiesta to work with new headunits if they also have bluetooth.

P.S. I'm not going to buy any additional amps. so please do not advise me of this.

Right just fitted my headunit so I can advise you on a few things!

Subwoofer to Headunit is normally RCA leads, your headunit will have a remote you need to wire into the Sub aswell, this tells it when to come on/off. Normally just a single cable that you splice together...

Speaker to Headunit again is normally RCA but can depend on the speaker and headunit

Stalk Adaptor is Quadlock to ISO with a lead splitting off to plug into the unit separately, check your Headunit is capable of taking it first there may need to be some wiring done alternatively some headunits have the capability of plugging straight into the back.

Mine didn't have the bluetooth so I'm not sure about the Mic, you won't need any Amplifiers your sub has one built in if it's an active