How can I stop being overprotective and let my only child grow?

He's nearly 14 months old and I admit to being overprotective. He's all my husband and I have; our only child. I gave birth for the first time at the late age of 18.

He already started walking (but is still improving with his balance and can tumble after several steps) and I hold him firmly after a while. Sometimes he screams. That's his way of saying "let me go, you're boring me". I know but I don't ever want him, my little boy getting hurt. Time flies fast and within 4-5 years later, he's going to start school and I'll have to let him go, wish him luck on his first day, hoping his classmates treat him kindly and he doesn't get hurt.

I even have gates installed so he can't access the kitchen and a metal gate on the kitchen window. I'll soon buy gates on all the other windows and anchor a furniture.

When he gets older, I'll eventually have to let him be independent. How can I stop being overprotective?

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9 d
I've seen too many news of every possible scenarios of little kids going to the park and not returning, drowning incidents because the parents didn't bother teaching them how to swim, a babysitter or daycare workers causing injuries or killing then, getting hurt by a bully because the parents never got him/her into martial arts, etc.
Updates
9 d
Typo. I gave birth at 38 years old... not 18 lol
How can I stop being overprotective and let my only child grow?
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