$ python letter_boxed.py --help
usage: letter_boxed.py [-h] [-l MAX_LENGTH] [-w WORDS_FP] [--box-words] letters

positional arguments:
  letters               Format: ABC-DEF-GHI-JKL

options:
  -h, --help            show this help message and exit
  -l MAX_LENGTH, --length MAX_LENGTH
                        Max solution length. Default: 2
  -w WORDS_FP, --words WORDS_FP
                        File containing words. Default: words_easy.txt
  --box-words           Output just the words that fit the box

See here for word list

https://github.com/raun/Scrabble/blob/master/words.txt

A couple links for solutions. I didn't read the code because that would be cheating.

https://medium.com/@pnmclaugh/solving-letter-boxed-in-python-5e6cc4b216f9

https://calebrob.com/algorithms/2019/01/15/nytimes-letter-boxed.html

More word lists below

https://github.com/aliceyliang/letter-boxed-solver

which links to

https://replit.com/@demonpuncher/New-York-Times-Spelling-Bee-Puzzle-Solver#words.txt

https://github.com/dwyl/english-words