>>105851411 (OP)It seems that the creator already posted the solution in the title.
You were supposed to convert the b64 to hexadecimal. The result should be 10 aa f7 23, which can be converted to an ip4 address 10->16 and so on to get 16.170.247.35
If you went to https:16.170.246.35:1337 it showed a button for you to click and how many people pressed that button. When I try to go back to the website it doens't let me, it might have gone down in that time, or the creator blocked ips if they clicked that button or something.