I know i cannot change my title but can i add keywords to my subtitle?

Hi everybody, Just got into KDP publishing this week, been binging YT vids all week. I am a Therapist. I published a book this week in a niche that i am closely personal with. Its for Christians in 12 step recovery. Its a 90 day devotional. I did it all in Claude Cowork. I have a lot of friends that i have told about it, so i am hoping to clear at least 10-20 sales this first week. I have no idea what i am doing, thats why I am here. I have a line up of 3 more books that can compliment this one, and Claude helped me create brand for more books. I am not when i should starts Ads, etc etc. I am also curious about "pen names". Anyway, so happy to be here, and cant wait to start reading all of your post, and experiences. I will add my book cover, what the pages look like and a link to the store to this post, looking for honest raw feedback. https://a.co/d/00CSlPd3

Can I use my affiliate link on my own books?