One of the most important aspects of surviving a harsh desert environment is PREPARATION.
https://www.desertusa.com/desert-activity/desert-survival-tips.html has a list of 26 tips for surviving in the desert. So, if in the fictional world you are creating, your characters make a choice to pass through, travel to, or live in a desert environment, this resource will provide plenty of preparatory ideas for you to have your characters utilize.
However, if your characters find themselves in a desperate, emergency situation you may need survival tips rather than preparation tips.
The next source you can dig into is https://www.skilledsurvival.com/desert-survival-tips/ . Here you will find suggestions for dealing with flash floods (rare, but REAL), dust storms, and the like, as well as learning that getting water from a cactus is NOT necessarily a good idea.
https://www.backpacker.com/skills/rip-live-survive-desert-extremes/ provides some additional tips as well as some hazards to keep on the lookout for. This site also provides navigational tips that may prove useful to the characters in your story.
The next source shares information on what plants could be utilized as food as well as the different TYPES of deserts around the planet. This will be exceptionally useful if your story is based in another world or universe, either fantasy or science fiction. https://www.survivalworld.com/survival/desert-survival/ The information here will give you plenty of basics that you could adapt for your fictional world.
These sites will provide you with plenty of facts and inspiration for your desert worldbuilding. Happy Writing everyone!