how to pass csrf-token in first request

my question is how cookies works, this question is arrived in my mind when i loaded my page for first time i got this

REQUEST HEADER
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3
Accept-Encoding: gzip, deflate, br
Accept-Language: en-GB,en;q=0.9,en-US;q=0.8
Cache-Control: max-age=0
Connection: keep-alive
Cookie: csrftoken=gsZxmbW4XUpE6YnaQhlrAx9JduyExVgzWEo4fXhcY4V3fbHWVtwf0msbDQDT5r43
Host: 127.0.0.1:8000
Upgrade-Insecure-Requests: 1

when first request was sent it already had csrftoken in cookie

i tried same in incognito window than also i got same result. how can my browser already have cookie without any communication to server

i am working on django with angular 7, problems is that i am sending my request from angular

 this.http.post('http://127.0.0.1:8000/',data,  {observe : "response", withCredentials: true } )}

but in response of that i am not getting any csrftoken in setcookie .

please help me ..... sorry for adding two problems in one question but both are indirectly connected to each other