(Replying to PARENT post)
I have not found yet any book that I consider really satisfactory, mainly because all of them are more or less incomplete, which is understandable, because a complete presentation would require a huge amount of work for rewriting the manuals for all the branches of traditional physics to use models based on geometric algebras.
An older decent introduction is "Geometric Algebra for Physicists" by Chris Doran and Anthony Lasenby.
There are also several older books, which need more mathematical experience, by David Hestenes, who was responsible for the revival of the theory of geometric algebras, which had previously remained a niche domain of mathematics for about a century after the too early death of their discoverer, William Kingdon Clifford.
There are also many more recent books, which can be seen e.g. through a search on Amazon or other such sites, but I have not searched such books during the last years, so I do not know which of them are good.
The older books are good enough to provide an understanding of geometric algebras, but for practical applications one usually must go beyond them.
Even without applying in practice the theory of geometric algebras, it is still useful to understand it, because this removes most of the mystery from mathematical physics and it allows a more efficient organization in your head of the knowledge about it.
(Replying to PARENT post)