First, open a web browser and go to the Google Translate website. Click on the Documents tab at the top of the page. Select the current language of your PDF document and the language you want to translate it into, which in this case is Spanish. Then, click on the Browse button to upload your PDF file. Google Translate will then translate the text in your PDF document into Spanish. You can then download the translated PDF file.
Alternatively, you can also use Google Drive to translate a PDF document. Open your Google Drive account, upload your PDF file, and right-click on the file. Select Translate document from the drop-down menu. Choose the language you want to translate the document into, which in this case is Spanish. Google Drive will then translate the document and save it as a new file in your Google Drive account. You can then download the translated PDF file.
I hope this helps! Let me know if you have any other questions.