Brass instruments were the first I learned back in grade school. Then, I self-taught guitar and bass guitar in high school before deciding one day, just a couple of years ago, to pick up the instrument I always REALLY wanted to play - the saxophone.
Listen, I bought an alto sax and I fretted (pun intended) over wasting the money without any knowledge of the instrument so bad, I learned the full saxophone 2 1/2 octave scale in one day.
I was fortunate to have deep musical training in a high school for the arts back in the '60s, back when this country still had it's head on a little straighter, which I had already used to learn guitar, so I was confident I could do the same with the sax.
I downloaded a chart of saxophone fingerings (readily available anywhere on the internet) and it looked like the instructions to operate a space ship the first time I saw it. It was daunting, to say the least. But the fear I had over buying an instrument I had no experience with motivated me and once I had my sax in hand the fingerings became clearer. I always believed that once you know the full chromatic fingerings of any monophonic instrument, all that's left to master the instrument is practice, practice, practice.
Fingerings on polyphonic instruments like guitar or piano are different. The notes are right in front of you instead of somewhere in the air before you play them and you can accompany yourself on polyphonics.
Also, and this should boost your confidence, my brass embouchure segued right into the woodwind embouchure with little trouble at all. So, if you've been practicing brass regularly, you might be surprised at the ease of the switch to reeds as far as embouchure is concerned.
I am a very strong sight reader. but I had trouble at first with playing sax fingerings because my brass fingerings were so entrenched in my mind for so many years, my brain and my fingers were in a constant state of war!
I tried my best to stop thinking about the brass fingerings at all and practiced for hours every day without fail for weeks, months and now a couple of years until sax fingerings were as imbedded in my mind as the brass fingerings.
Then, I found out about Joe Allard and his disciple Harvey Pittel online with his fantastic sax instruction videos on YouTube and was transformed. Google Harvey. Follow his advice.
GO FOR IT! Learning a new instrument benefits the mind, body and soul. You will not be sorry!!!