Why am I unable to get a girlfriend?

I've been hearing the saying “everything comes at its own time" but in my case it's taking forever. I don't even know what's right anymore.

When I see a girl I like, I feel so heavy to say a word, this has happened to me like 10 times already.

Till now I still don't have an experience of what a relationship is, so tiring.

What do you think is wrong? Please advise me
Why am I unable to get a girlfriend?
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