[tags reading: i wonder what's up with the 18 and 92 but... i do not need and probably do not want to know]
This is the completely wrong mindset. People definitely need to know why certain symbols are used as dogwhistles and what the history/context of those symbols is. Don't just blindly start avoiding them without educating yourself, don't just follow orders without thinking just because they are given by a source you were told is on the side of the "good guys". I literally can't stress enough how blind obedience is bad no matter which side you're on.
A lot of the symbols shown here have a history that was completely harmless, or they were religious symbols, letters of the runic alphabet, or just simple meaningless numbers, before nazis started appropriating them and using them as dogwhistles. 92 is short for 1992, the year in which a famous hate group was formed by neo-nazis. It is also a simple date, for example I was born in 1992. The hate group's name is Combat 18. 18 is a number commonly used by nazis because it symbolizes the first and eight letter of the alphabet - 1 for A (Adolf) and 8 for H (Hitler). 88 has a similar meaning - the double H it stands for can be seen as an abbreviation for Heil Hitler (the nazi salute). It was also a caliber of cannon commonly used by the nazi military (88mm, or 8.8cm).
Examples of symbols that can have different meanings if slightly differently presented are the second symbol in the second row (the rune Othala, which is simply just a letter, but the little upward pointing lines are specifically how nazis draw it. Pagans don't add these normally, we avoid this on purpose) and the skull directly underneath it (skulls and bones are popularly used as a symbol for piracy or in morbid aesthetic art, but this specific skull and bones was the insignia of a nazi SS unit), and to the right of it the iron cross (which is also simply the insignia/logo of Germany's current, modern military. With straighter edges, it was used by the German military in WW2).
If you don't know these things, how will you be able to spot the difference between the symbols being used in their "intended" way, and them being used as a dogwhistle? You can't. This applies to every topic, not just nazi dogwhistles by the way: don't blindly follow, don't just believe without asking questions, and always do your own research.