After murdering Han Solo, many people think that Kylo Ren cannot be redeemed. However, there are some things to consider before reaching a final verdict. There were other dark side practitioners in the Star Wars Universe who found redemption despite all the evil they had done. The most famous example is Darth Vader, who had killed countless people in the Galactic Empire’s name. Also, Kylo Ren may have killed his father, but let’s not forget that Darth Vader did bad things to his family too. He strangled his wife with the Force (which led to her death by childbirth), he blew up his daughter’s adopted world, he froze his future son-in-law in carbonite, and he chopped off his son’s hand. Despite all of that, Darth Vader found redemption by sacrificing himself to save his son from Emperor Palpatine. Plus, Kylo Ren has shown great conflict within himself so there is still a chance he could find redemption like his grandfather did. So, I would not count Kylo Ren out yet in terms of redemption.
Darth Vader also killed possibly hundereds of children during order 66 in the Jedi Temple. If he can be redeemed for that then Kylo Rem can definietly be redeemed for killing his father.