Take the front brake off. Take it apart carefully & use wire brush, scraper & emery paper to remove corrosion away. You can use rust remover on the non aluminium parts. Reassemble with waterproof grease (even regular automotive grease is better than nothing) applied between the parts that move against one another, and on threads.
Voila, your brake will work like new.
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Get a bicycle. You will certainly not regret it, if you live.