What works for you, might be impossible for someone else. Some are simple to use, but limited in capability, while others have so many tools, it can be overwhelming to try without some familiarity with it.
Some specifically designed as map making programs, many as graphic design or 3D applications. There are dozens of applications available. If hand-drawing is problematic for you, then software is your solution.
You know what you want to create in your head, but putting it a format that your players will understand can be challenging. However, not everyone is skilled at drawing. Some people can grab and pencil or pen and create a workable map in a few minutes, some can create artistic masterpieces doing the same. From world to encounter scale, maps let players know where they are in the imaginary worlds of your games. Maps let players know how their surroundings appear around them. Part of the job often includes creating one or more maps. Gamemasters have a serious, unpaid job on an ongoing basis to create exciting plots and stories for their friends and players.