50 bucks? Tough to find a big tablet for that price. Maybe something second hand, and with a cracked screen (or otherwise compromised).
At $100, some more options open up on Amazon, like this one:
https://www.amazon.ca/Storage-Tablet...df_B0B2RLTDH8/
But still, the biggest you'll find for this price is a 10in screen and I would expect those cheap tablets to be low quality, slow, and have poor battery life.