Simple form

Simple form: forms.Form

forms.py

class FormEmail(forms.Form):
    email = forms.EmailField(widget=forms.TextInput(attrs={'class': 'form-control', 'placeholder': 'Email'}))
    subject = forms.CharField(required=False, widget=forms.TextInput(attrs={'class': 'form-control', 'placeholder': 'Subject'}))
    email_note = forms.CharField(widget=forms.Textarea, required=False)
    include_price = forms.BooleanField(required=False, widget=forms.CheckboxInput(attrs={'class': 'form-check-input',}))

To add a text area field it is necessary to add it as CharField and set the widget to Textarea: widget=forms.Textarea

views.py

from django.core.mail import send_mail
from .forms import FormEmail

Update the existing fossil view. Inside the function add:

if request.method == "POST" and "send_email" in request.POST:
    form_send_email = FormEmail(request.POST)
    if form_send_email.is_valid():

        text_subject = f'{fossil.fossil_name}'
        subject = form_send_email.cleaned_data['subject']
        if subject:
            text_subject = f'{fossil.fossil_name} - {subject}'

        text_price = ''
        price = form_send_email.cleaned_data['include_price']
        if price and fossil.fossil_value:
            text_price = f'<p>{fossil.fossil_value}</p>'

        text_note = ''
        note = form_send_email.cleaned_data['email_note']
        if note:
            text_note = f'<p>{note}</p>'

        text_description = f'{fossil.fossil_name} '
        if fossil.fossil_description_short:
            text_description += fossil.fossil_description_short
        if fossil.fossil_description_detailed:
            text_description += fossil.fossil_description_detailed

        html = f'''
                <html>
                    <body>
                        <div>
                        <h1>{text_subject}</h1>
                        {text_price}
                        {text_note}
                        {text_description}
                        </div>
                    </body>
                </html>'''
        
        from_email = "squirrelsandbeavers@gmail.com"
        email = form_send_email.cleaned_data['email']
        to_email = (email, )
        try:
            send_mail(subject=text_subject, message="", from_email=from_email, recipient_list=to_email, html_message=html)
            messages.success(request, f"Email to {email} sent successfully.")
        except Exception as e:
            messages.error(request, f"Error, email not sent. {e}")

        return redirect('fossil-selected', pk=fossil.id)
    else:
        messages.error(request, f"Error, email not sent.")
        return redirect('fossil-selected', pk=fossil.id)
else:
    form_send_email = FormEmail()
    
return render(request, 'app_fossils/fossil.html', {
    ...
    'form_send_email': form_send_email,
    ...
    })

Template: fossils.html

<a class="btn btn-sm btn-outline-secondary d-inline" data-bs-toggle="collapse" href="#collapse_Send_Email" role="button" aria-expanded="false" aria-controls="collapse_Send_Email" style="text-decoration: none;">Send fossil ▼</a>
    <div class="collapse mt-3" id="collapse_Send_Email">
        <div class="card card-body p-1 border-0">
            <form method="POST">
                {% csrf_token %}
                <p>{{ form_send_email.email }}</p>
                <p>{{ form_send_email.subject }}</p>
                <p>{{ form_send_email.email_note }}</p>
                <p>{{ form_send_email.include_price }} Include price</p>
                <button class="save btn btn-sm btn-outline-secondary mt-3" type="submit" name='send_email'>Send</button>
            </form>
        </div>
    </div>