How to call script include from the client script servicenow?

Can anyone help me with how to call the script include from the client script?

function onChange(control, oldValue, newValue, isLoading, isTemplate) {

    if (isLoading || newValue === '') {
        return;
    }

    //Current assignment group
    var assignment_group = newValue;
    if(assignment_group){
        var coe = '';
        var ga = new GlideAjax('sn_hr_core.scriptIncludeNameUtils'); //Script include
        ga.addParam('sysparm_name','MethodName'); //Method/Function
        ga.addParam('assignment_group',assignment_group); //Parameter
        ga.getXMLAnswer(function(response){
            coe = response;
            if(coe){
                g_form.setValue('u_hr_coe', coe);
            }
        });
    }
}

Script Include:

MethodName: function (assignment_group) {
    var sys_id = this.getParameter('assignment_group') ? this.getParameter('assignment_group') : assignment_group; //Params
    var result = '';
    if(sys_id){
        var grSysChoice = new GlideRecord('sys_choice');
        grSysChoice.addEncodedQuery("element=assignment_group^name=sn_hr_core_case^dependent_value="+sys_id);
        grSysChoice.orderBy('sequence');
        grSysChoice.setLimit(1);
        grSysChoice.query();
        if(grSysChoice.next()) {
            result = grSysChoice.getValue('value');
        }
    }
    return result;
},

We need to use GlideAjax to call script include from client script.

var ga = new GlideAjax('sn_hr_core.scriptIncludeNameUtils'); //Script include
ga.addParam('sysparm_name','MethodName'); //Method/Function
ga.addParam('assignment_group',assignment_group); //Parameter
ga.getXMLAnswer(function(response){
    coe = response;
    if(coe){
        g_form.setValue('u_hr_coe', coe);
    }
});

Youtube video for Ref: https://youtu.be/zNGdVSCGggE