1. Fake it 'till you make it!
There's a saying in English, "Fake it 'till you make it." It means to pretend to be good at something, and pretend to feel confident. As you continue and build your skill, your fake confidence will be replaced by real confidence.
When you get a chance to speak to people in English, take it! Stand up straight and tall. Jump into the conversation and speak as if you're completely fluent.