How do I improve coding interview question?

I'm preparing for my first FrontEnd Web Developer job, I had practiced my JavaScript skills by building many small and few larger projects and I just fell confident about it but when it comes to coding challenges types of problems I still fell totally blank on how to solve it :(

Any way how can I get good on such type of problems?

PS: I'm from non science background but I'm learning basic concept of Algo & DS
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