Vector illustrations can be edited and scaled to any size without loss of resolution using Adobe Illustrator or other vector editing programs. Adobe Illustrator is the industry standard for opening and editing EPS vector files. If you want to use a Shutterstock EPS vector but do not need the editing and scaling functionality, you can either save it as a JPEG from the site or open the EPS file as a JPEG image in Photoshop. Here's how to do so:
Opening an EPS file with Photoshop
Download the EPS file to your computer
Open Photoshop, choose File > Open, and select the EPS file that you downloaded
Choose your dimensions and resolution; at least 300 dots per inch is recommended for print
Choose CMYK for print or RGB for web or TV
Select Constrain Proportions to maintain the height-to-width proportions and click OK
For example, a vector EPS file might be 4" x 4" in its native size, but you might need it larger. You can open the file in Photoshop and change the Image Size to 45" x 45" at 300 pixels/inch. After clicking "OK" the vector will be resized and you can save the file as a JPEG. You will now have a large file with no loss in quality.
These steps might be slightly different depending on your version of Adobe Photoshop.