JSFiddle - React, Tailwind, and code Playground

HTML

<form name="billdata" id="billdata"  enctype="multipart/form-data" method="POST" onSubmit="javascript:return checkForm();">
       <div class="input-group bmargindiv1 col-md-12">
        <span class="input-group-addon ndrftextwidth text-right" style="width:180px"> Name :</span>
         <input type="text" name="u_name" id="name" class="form-control" placeholder="Add Name" onKeyPress="clearField('name');">
        </div> 
        <div class="input-group bmargindiv1 col-md-12">
        <span class="input-group-addon ndrftextwidth text-right" style="width:180px">Email :</span>
        <input type="email" name="u_email" id="emailid" class="form-control" placeholder="Add Email Id" >
         </div>
        <div class="input-group bmargindiv1 col-md-12">
         <span class="input-group-addon ndrftextwidth text-right" style="width:180px">TYPE OF COMPLAINT
     :</span>
        <select class="form-control"  id="compleant" name="complainType" onChange="javascript:checkComField();">
         <option value="">Select types of complaint</option>
         <option value="card">Card Related</option>
         <option value="claim">Claim Related</option>
         <option value="product">Product Related</option>
         <option value="Premimum">Premimum Related</option>
        </select>
        </div>
<input type="submit" class="btn btn-success" name="complainSubmit"  id="addProfileData" value="Add"/>
    </form>

JavaScript

function checkForm(){ 
    var s=document.billdata;
    
    console.log('compalin',s.complainType.value=='');
    if(s.u_name.value==''){
        alert('Please enter name');
        s.u_name.focus();
        s.u_name.style.borderColor = "red";
        return false;
    }else if(s.u_email.value==''){
        alert('Please enter email');
        s.u_email.focus();
        s.u_email.style.borderColor = "red";
        return false;
    }
    else if(! validateEmail(s.u_email.value)){
        alert('Please enter a valid email');
        s.u_email.focus();
        s.u_email.style.borderColor = "red";
        return false;
    }
    else if(s.complainType.value==''  ){
        alert('Please select the type of complain');
        s.complainType.focus();
        s.complainType.style.borderColor = "red";
        return false;
    }else{
    }
}

function clearField(name)
{
//do something

}

function validateEmail(email)
{
return true;

}