Recently I got my first arduino uno also with a compatible lcd. I've soldered the lcd well and connected it to the arduino. After several successful tries, I noticed that I can create custom characters. Out of curiosity, i wanted to make the Captain Marvel's logo on the beeper shown in the post movie from Avengers : Infinity war, as the lcd looked lowkey similar :). Therefore, i created several custom characters for the star, but I can't make more caharacters for the ribbons. Can anyone advise on how to create more characters, or how to manipulate the arrays inside the loop. Thank you!
You have eight custom characters.
Whether or not you can make anything out of the common Kanji character set ... well. 
