The short answer is, yes, those of us interested in the Silmarillion have probably read it and related books over and over again several times. But the sheer volume of names, places and dates can be overwhelming.
There are several passable guides that have been published (in addition to the index/glossary at the end of the book). They all have flaws, so I'm not inclined to recommend any in particular.
There is an on-line wiki, which I cannot vouch for in any way. It does have a First Age timeline (beginning with the first rising of the sun) that might be helpful.
https://lotr.fandom.com/wiki/First_Age
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