Dear Angel Tsang,
There is no information on your profile to use in developing and tailoring an answer for you, but I did learn a bit from your list of questions...and I have a suggestion for you:
Locate non-profit organization(s) of interest, and join them as a volunteer. When you have demonstrated your reliability, then offer to organize an event for them. Soon you will build a wonderful resume to show an employer.
I have organized events in my work as a cytologist, also for a homeless network here in Washington State, and then a series of trauma seminars for a charitable organization in Iowa working with women after prison.
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I have never worked as an event manager, but if I were job-hunting in that field I would have an excellent resume and outstanding references to show an employer.