Password protected single page

Hi
Is there any option to make only single page password protected page
Which i have tried to adding
Raw HTML , js and CSS file
I am getting an error
Password function is not working

Here is all code which I am trying
If anyone can help me
Thanks in advance

Vip Dental
<br>  <div class="container">

logo

This is a Password protected page.
Therefore, we provide only limited access.

<input type="text" class="passwordField" placeholder="Enter password">

<br><br>
<input type="submit" class="submitButton" value="Unlock">


Click Here to see Pricebook

a.visited
{
background-color: #f44336;
padding: 10px 25px;
text-align center;
display: inline block;
font-size:2rem;
display: block ;
cursor:pointer;
}

.authenticateForm {
display: ;
font-size:2rem;
margin: 0 auto;
text-align: center;
max-width: 600px;

}

.protectedContent {
height: ;
width:100% ;

display: none;
width: 100%;
margin: 0 auto;
background: lightpink;
padding: 15px 20px;
border-radius: 1px;
text color: white;
font-size: 3rem;
text-align:center;
font-weight: 500;
transition: all 0.2s ease;
letter-spacing: 0.018em;
line-height: normal;
display: inline block;
outline: 0;
}

.submitButton {
width: 70%;
margin: 0 auto;
background: #ff7a09;
padding: 15px 20px;
border-radius: 2px;
color: white;
font-size: 2rem;
font-weight: 900;
transition: all 0.2s ease;
letter-spacing: 0.018em;
line-height: normal;
display: inline block;
outline: 0;
border: none !important;
}

.submitButton:hover {
cursor: pointer;
outline: 0;
width: 70%;
}

.passwordField {

width: 100%;
margin: 0 auto;
background: #ff7a09;
padding: 5px 90px;
border-radius: 1px;
color: white;
font-size: 2rem;
font-weight: 500;
letter-spacing: 0.018em;
transition: all 0.2s ease;
line-height: normal;
display: inline block;
outline: 0;

}

.passwordField:hover {
border-bottom: solid #ff7a09;

cursor:pointer;
outline:0;
}

.errorMessage {
margin: 15px auto;
font-weight:600;
font:bold;
font-size:2rem;
line-height: normal;
max-width: 400px;
color: #ff7573;
}

.ndeMessage {
font-size: 2rem;
font-weight:700;
margin: 15px auto;
line-height: normal;
text-align: center;

}

Hi,

Contact with your purchase item author hope they will helped!

Thanks!