How to display the fields I want at a theme header

I am creating a custom theme.
I want the fields IssueDate and InvoiceNumber just to appear at the header of the theme with customized labels (not the invoice end date). How can I make it?

learn or hire person who know liquid language.

Ok. I know liquid. What I don’t know is the field names. Can you tell me? I want invoice date and invoice number.

{% for field in fields %}
                    <div style="font-weight: bold">{{ field.label }}</div>
                    <div style="margin-bottom: 10px">{{ field.text }}</div>
                    {% endfor %}

invoice date and invoice number. is controlled by this. do the hit n trial method.

Thanks @manishkumarshivam.
Fixed it:
Knowing that when the invoice is printed, it prints the fields like that:
Invoice Date
dd/mm/yyyy
Due date
dd/mm/yyyy
Invoice Number
99999

I want to eliminate Due date and make the labels of ‘Invoice Date’ to just ‘Date’ and ‘Invoice Number’ to just 'Number.

So I did the following that worked:

`{% for field in fields %}

 {% if field.label == 'Invoice Date' %}  
      <div style="font-weight: bold">Date</div> 
      <div style="margin-bottom: 10px">{{ field.text }}</div>
 {% endif %}
 {% if field.label == 'Invoice Number' %}  
      <div style="font-weight: bold">Number</div> 
      <div style="margin-bottom: 10px">{{ field.text }}</div>
 {% endif %}

{% endfor %}`