How can a shy woman become a trainer or lead and finally get promoted?

I’m shy but I’m confident enough be a lead & train new hires. I don’t like to sit in one spot hidden in an office, I like to move around for work like walk & watch the hires, train them like a lead is something I’m interested in but I need be given a chance not deny me as she is quiet or shy.
at my current job I ask to be trainer but they don’t want give me promotion even tho I’m old many times I’m good fast worker. I’m on verge quit as I want grow not stuck same role forever or not get promotion out of jealousy.
what can I do?

I currently work at a clothing warehouse.
my whole life people look at me and don’t take me serious I think people don’t see me as a mature woman. I’ve been to many job interviews wen I was 18-20 & I neevr got the job, and I would get denied jobs if I show up to interview dressed up with makeup. I get denied office jobs & retail clothing jobs at mall.

How can a shy woman become a trainer or lead and finally get promoted?
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