WordPress Error 500 is an internal server problem in WordPress that is a common issue among users. If theres exhaustion in the PHP memory or corrupted .htaccess file, then you might face this sort of error. When you get this internal server related problem, you need to find the root cause of the error to fix it. One of the most common causes of this error is the limit in the PHP memory. If this is happening with you, then you need to exceed the memory up to the standard limit of memory as beyond this, you cannot increase the memory. The host and WordPress usually set the PHP memory limit, so you need to increase the memory according to this only.
Sometimes plugins can also be a disturbing element for the smooth functioning of WordPress. If they are faulty ones, then you must consider deactivating the plugins. But, make sure to do this one by one to find out which plugin was causing the trouble to you. There are many other solutions that you can try if these above-mentioned solutions dont work out for you.