Yes, You need software to edit these designs. You can use any software which supports PSD or AI files. We listed below some useful software which are perfect to edit our designs.
You can use some other software but these are our official recommendations.
We recommend using Illustrator for maximum editing capability but you can start with Inkscape if your budget is limited. Inkscape is a professional vector graphics editor for Linux, Windows, and macOS. It's free and open source. Feel free to visit https://inkscape.org/ for more details and download it.