Hello, thank you for taking the time to post your question!
To convert 1001 to a base four numeral you want to follow a series of steps
1001 / 4 = 250 with remainder of 1
250 / 4 = 62 with a remainder of 2
62 / 4 = 15 with a remainder of 2
15 / 4 = 3 with a remainder of 3
3 / 4 = 0 with a remainder of 3
Then you take the remainders from the bottom to the top to get the number of 33221
I hope that helps you get moving in a better direction on this type of question! Feel free to reach out if you have any additional questions beyond that :)