Without knowing the specific tap you are asking about, it's impossible to guess which method would work for you. Generally, it would probably involve removing the knob that's attached to the valve which will either screw on or be held in place by a grub screw. When the knob is removed you will have access to the valve and be able to see where to use a spanner to unscrew it from the tap body.
Rupert
May 2020
Automatic Answer
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