In this first step: From within your Wordpress Dashboard, you'll see the media tab on the left hand side, along with all your other menus.

Click on the Media button and then select 'Add New' ... You'll then be presented with the following page :-

Now you can either drag and drop files into the upload area, or clicking on select files, which will open up a search area on your computer.

Navigate to where your files are stored and then select the image you want to upload to wordpress.

If you have more than one file at a time to upload, you can select them by holding down your Control Key (CTRL) on your keyboard, while you select the files you wish to upload. Once you have your chosen files to upload, select 'Open' and this will start the upload process to wordpress.

Once your file is uploaded, let's take a look at how we position it into a page or post ...