My_Test_Repo/force-app/main/default/lwc/p2cSliderComponent/p2cSliderComponent.js

import { LightningElement,api } from 'lwc';

export default class P2cSliderComponent extends LightningElement {
    val= 20
    changeHandler(event){
        this.val = event.target.value;
    }
    @api resetSlider(){
        this.val = 50;
    }

}