As the name suggests, simple web is rather simple
URL: http://dctf1-chall-simple-web.westeurope.azurecontainer.io:8080/
Submitting this returns
Not authorized
Looking at the post request:
flag=1&auth=0&Submit=Submit
Simply changing auth to 1 returns the flag:
There you go: dctf{w3b_c4n_b3_fun_r1ght?}