Which connection string am i supposed to use/choose?

[Imeguras]

So basically i decided to let mongodb host the database by themselves with the free/shared program the problem is they not only give three tipes of formats for the connection string (i've tried all of them) but in my last atempt i learned that you are supposed to define the database in the url in which i created one and placed the name in the url

Also i added in allow ips on mongoDB to 40.70.0.0/18 so that github can acess it
here's an example of one of the url's i've tried using
mongodb+srv://"theUsername":"thePassword"@cluster0.jm2nr.mongodb.net/"theDatabase"?retryWrites=true&w=majority
In the read me it kinda skips the whole process on how its supposed to look

[Imeguras]

mmmm i finally fixed it with by allowing every ip(0.0.0.0) instead oof the previous ip