Anyone please explain what is this and it's number are growing

[Vaslias]

Please explain me

What part of your body is that?

Chest

Age spots. Sometimes called liver spots.
they are harmless.

Thanks how to remove this

Lasers maybe. Or you might be able to get them frozen off.
keep out of the sun to reduce the risk of getting more. But if you’re prone to them, you will get more.

These happen more as you get older, sun damage and hormonal changes. SPF50 to limit further damage or keep covered up. See a dermatologist if you want them removed or reduced. It's the seborrheic keratosis you want to avoid, they go by the charming common name of geriatric warts.

You should always get things like this checked out by a GP, especially if raised.