You can customize the titles of specific fields on your SharePoint list forms (Display, Edit, or New) using CSS.
Each field is assigned a unique class name, which makes it easy to target and style or rename them.

For Example : Title field will have a unique CC Class name « kw-field-Title »

Follow the steps bellow:

1. Identify the Field’s Class Name
   1. Open the form (Display/Edit/New) where the field is located.
   2. Right-click on the field title and select Inspect (this opens your browser's Developer Tools).
   3. Look for the unique class name.
      1. For example: The 'ItemOwner' field may have a class like kw-field-ItemOwner.
         
         
         
2. Access the Style Editor - open one of the list items in view/edit form.
   1. Click the gear icon on the top-right side of the form and select Styles.
      
      
      
   2. In the opened Styles Editor, add the following CSS styles to modify the field title:
      

      .kw-field-Title label {
          visibility: hidden;
          position: relative;
      }
      .kw-field-Title label: before {
          content: 'Here is another field title';
          visibility: visible;
      **}

       

   3. You can see that the text should be in « content » CSS attribute.**
      You can add such styles for any field you want to change the caption, you need just replace « kw-field-Title » class name with the right one.
      
3. Make any other changes and click Save