In the Chrome DevTools, under the Network section, right-click on the line you are interested in and select the appropriate type of copy from the context menu:

An example clipboard content looks like this:
Copy as cURL
curl 'https://stackoverflow.com/posts/25291052/editor-heartbeat/answer' \
-H 'authority: stackoverflow.com' \
-H 'pragma: no-cache' \
-H 'cache-control: no-cache' \
-H 'sec-ch-ua: "Google Chrome";v="89", "Chromium";v="89", ";Not A Brand";v="99"' \
-H 'accept: application/json, text/javascript, */*; q=0.01' \
-H 'x-requested-with: XMLHttpRequest' \
-H 'sec-ch-ua-mobile: ?0' \
-H 'user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.114 Safari/537.36' \
-H 'content-type: application/x-www-form-urlencoded; charset=UTF-8' \
-H 'origin: https://stackoverflow.com' \
-H 'sec-fetch-site: same-origin' \
-H 'sec-fetch-mode: cors' \
-H 'sec-fetch-dest: empty' \
-H 'referer: https://stackoverflow.com/questions/25291052/how-to-view-the-whole-raw-http-request' \
-H 'accept-language: en,pl;q=0.9,es;q=0.8' \
-H 'cookie: prov=8a6c8983-02cd-669c-367d-61ff657f111e; _ga=GA1.2.1494864357.1594965293; __qca=P0-618917173-1594965293194; __gads=ID=86eda01ab828f223:T=1594965534:R:S=ALNI_MZ6mV2_oJewkg2Z7wubZCCK_dFI0Q; gadsTest=test; sgt=id=9653ade3-9325-4178-a074-d2ff62012690; _gid=GA1.2.480664929.1621240994; acct=t=PYE1PDFUezJZN%2b7eJHz4uQtgdkSgmrsw&s=NfLIf8YH%2f3FPmxGoaPDa2w5sB%2bzihVsv' \
--data-raw 'fkey=39c9ef4d76e1af44087482fe5f9802ac518ce9725a5323015874a7e69a493dea&clientCount=4' \
--compressed
Copy as fetch
fetch("https://stackoverflow.com/posts/25291052/editor-heartbeat/answer", {
"headers": {
"accept": "application/json, text/javascript, */*; q=0.01",
"accept-language": "en,pl;q=0.9,es;q=0.8",
"cache-control": "no-cache",
"content-type": "application/x-www-form-urlencoded; charset=UTF-8",
"pragma": "no-cache",
"sec-ch-ua": "\"Google Chrome\";v=\"89\", \"Chromium\";v=\"89\", \";Not A Brand\";v=\"99\"",
"sec-ch-ua-mobile": "?0",
"sec-fetch-dest": "empty",
"sec-fetch-mode": "cors",
"sec-fetch-site": "same-origin",
"x-requested-with": "XMLHttpRequest"
},
"referrer": "https://stackoverflow.com/questions/25291052/how-to-view-the-whole-raw-http-request",
"referrerPolicy": "strict-origin-when-cross-origin",
"body": "fkey=39c9ef4d76e1af44087482fe5f9802ac518ce9725a5323015874a7e69a493dea&clientCount=4",
"method": "POST",
"mode": "cors",
"credentials": "include"
});
We also have the option to retrieve a specific response or all requests from the list at once using one of the "Copy all as ..." options.
Try it yourself and choose the most suitable option for you.
This site inspired my answer.