If you are on Windows 10 or 11, you already have a tool that can do this.

Click where you want the text to go. A box will appear where you can type.

Adding text to a PDF file like is straightforward and can be done for free using built-in software or online tools. You generally do not need to buy expensive software for basic text additions. Method 1: Windows (Microsoft Edge)

In the top toolbar, click the Add text (T icon).