I am struggling to understand how Bitcoin is going to be used.
I know its long standing coin, gold like qualities, not hackable etc. But when it comes to how it can be used, I could not find any answer. High transaction fee, limited coins cause deflation, too volatile etc. General public, corporations cannot use it. Gold is different, there is nothing like gold but we have better coins than this.
Will this be used for only speculation, betting? How would general public / institutions use it in future?
You answered it yourself really. Gold is valuable because of its scarcity and special properties. Bitcoin is similar. Bitcoin is limited, and can the very helpful utility of being able to be stored securely and sent easily to anyone for what is actually a pretty low cost.