@Maddybryce yes, you can do a loop with an odd number of strings. If you search "odd number of strings loop" you'll find a video by MashaKnots and one by AlexInnovations in which it's explained. I'm sure there are videos by other creators too. Another option to do loops for alphas with an odd number of strings is to include the leading string in the loop and use the other end of the leading string as the 13th base string.
If you want to make it 12 base strings I recommend removing the most left base string. I think it would look best this way.
I really shortened and changed this pattern to make it a keychain. I love this pattern and its the first alpha bracelet that looks good. so, thank you.