Well to answer your other question regarding Satan worship and symbolism, most of the symbolism that are used both in Freemasonry and the Occult are coincidental. Because there is such a long history for Masonry, a lot of the symbolism was used far before any of the others and some were taken from others and used in Masonry (there are several influences that were brought into the teachings as many Brothers sought Light and brought it back into the Fraternity's teachings.
As for your Journey, it will be entirely unique. You will find that each Brother views many similar teachings and symbols completely different and the beauty is that you only need to apply what you believe is proper Light for your Journey. You'll understand more once you are Initiated and get deeper into the history and teachings.
As far as Satanism and Freemasonry. The Church of Satan and many Occult groups directly used Masonic symbolism in their teachings far after they had been applied in Masonic teachings. The important thing to remember is that Freemasonry used it first for their own purposes and that other groups used the same or similar symbolism (either from Masonic teachings or from the originators of the symbols, many times the latter). This is not the same as the symbol meaning the same thing. It is all about interpretation and just because somebody is using the same thing for a negative, evil, or unappealing purpose...doesn't affect the original use in Masonic teachings.
Rest assured, you will be in control of your interpretation of the teachings and principles of Freemasonry. You will swear to uphold the rules and regulations, etc. of Freemasonry, but that does not in any way mean that you will be forced to interpret symbolism in a certain way. It is your Journey, and I wish you the best of luck and pray that you will enjoy it far more than I have so far. It will do you great things and you will do great things for the future of Freemasonry. Thanks for asking, Friend.