Hey, buddy! It will fit if you use LST and SCROG techniques! If you're growing AUTO, then no problem! You might have issues with feminized girls, as a long vegetative period will lead to a very large plant in flowering, and you won't have enough space; you could have big problems or just cut branches and deprive yourself of future harvest for whatever is left! 👆
With such a box, just autoflower + LST + SCROG + 15-liter fabric pot! 1 plant and you'll be happy and satisfied! Get a 100W max LED light! 👆 You can go for a multi-spectrum one.
Good luck, bro! ✊😇