And what are your most useful tips to make sure they will be friendly with other dogs?
Someone I knew has a dog that runs around the block and comes back by themselves, and will not listen to the owner calling them back. I do not want that.
I’ve been to a country where I saw no dogs on leashes. Some dogs following owners lazily and slowly riding their motorcycles when the human didn’t feel like walking, but had to walk their dogs anyways. I want whatever assertive and respectful communication these owners and dogs have.
If you have some money for classes, it will be easier. Then practice at home every day, and while out walking. If they get ahead of you/pull, make them stop and sit/lay down next to you. Then continue on. This may be walking one step at a time until they get the idea btw. Lots of patience is needed. Be consistent, with words, tone, and expectations (Edit: and hand gestures too)