Those copper tails usually come attached to the tap. Compare your new tap to your old one before you start cutting things. You may find your new taps have flexible tails which would need connecting to a copper pipe using nuts and olives.
To release the copper pipes out of the plastic fittings you may need to twist the collar anti-clockwise and then push down on the inner ring to release the clamp mechanism inside the fitting.
Post a photo of your new tap(s) before commencing work and someone may be able to advise on best method of connection.
Removing the old tap is by means of undoing that long screw, which usually secures a horseshoe shaped locking plate to the underside of the sink/worktop.
To release the copper pipes out of the plastic fittings you may need to twist the collar anti-clockwise and then push down on the inner ring to release the clamp mechanism inside the fitting.
Post a photo of your new tap(s) before commencing work and someone may be able to advise on best method of connection.
Removing the old tap is by means of undoing that long screw, which usually secures a horseshoe shaped locking plate to the underside of the sink/worktop.