Everyone needs to sell, not everyone needs to negotiate
Many people confuse ‘negotiation’ with ‘sales’ when they describe what they want to do. Selling and negotiation are not the same thing. They share skills and elements in their approach, but are fundamentally different in the way they are executed.
Sell first, and negotiate only when you need to. In both cases, yes, you can learn ‘how to’, and practice and coaching will enable you to be more successful.