“Is there a way to join this elite/chosen group? If so
how?”
I don’t like your choice of words as I don’t think like that but I understand why you use them. We use the terms front lines, because every group in klal Yisrael is needed and adds as discussed. If you are being serious, then just know that when Moshiach comes he will thank every You for their part in bringing him ie making the world a G-dly place.
If you’d like to join the front lines I’d suggest to do whatever you can to help and be mekarev your fellow Jews, such as inviting not yet frum Yidden over for Shabbos, there are loads of things that anyone can do in that direction it’s just a mindset- help as many Yidden as you can do as many mitzvos as possible.
Work on yourself but don’t wait till you’re perfect before you help others. “If you know an aleph, teach an aleph”
Sulearn as much as you can about the geula and what you can do to bring it. I highly suggest the 2sefarim set of shaarei geula-hoemuna vhatzifia, and shaarei geula-hoemuna ymos haMoshiach. The more you know the more motivated you will be.
Learn chassidus so that you will be in touch with what your neshama is and who you really are, so that you don’t have an identity crisis when Moshiach comes, and you will enjoy the process so much more, and you will be able to identify all the giluim that you were just learning about till then, ie you will know what you are experiencing.