nmap -sV --open -oA nibbles_initial_scan TARGET
 
" ======== about command ========
  -sV : service enumeration scan agains teh default port 1,1000 ports.
  --open : only return open ports.
  -oA : include XML output, greppable format, and text output. 
  nibbles_initial_scan
  TARGET : domain or ip target
"

Check which ports Nmap scans

nmap -v -oG -
 
" ======== about command ========
  -v : verbose output.
  -oG : output scan in grappable format to stdout.
  - : scan location.
"