Welcome to YT
If your going to potty train for outdoors...you will need to start potty training all over again from the begining.
Make sure you remove his potty pad that he uses in the house now.
You will need to confined him in a play yard or crate....Take him out to potty every 2 hours or so...Start giving him a command like "go potty" when you take him out.
When you see him pottying outside say "go potty" keep saying it until he is done than throw a potty party LOL tell him what a good boy he is and give him a treat that he really likes...once he has done his bussiness than you can let him stay out of his play yard for a while but keep an good eye on him....he will pick it up...it does take time...sit them up for success don't give him a chance to have an accident
If he doesn't do his bussiness when you take him out...put him back in his confined space and wait 15 to 30 minutes and try again.
I have a 20 week old pup...he now lets me know when he needs to go outside by sitting and barting at me, as soon as I look at him and say need to go potty he goes nuts and runs to the door....Good luck