How to help your dog become RESILIENT!First and foremost, before any training sessions be sure to meet your dog's needs. Basic needs include food, shelter, water, and a feeling of safety. But dogs have many more needs that need to be addressed before they are ready to learn and work as a team; exercise, entertainment, enrichment, relationships, etc. Make sure you are meeting their needs before you do any type of adjustment to training around distractions.
Second, all dogs have a basic need for feeling safe. If they've have previous trauma or if they are new in your home, you have to give them time to adjust and process all that has transpired. A dog that has had a significant trauma may take months, even years to feel safe in your care. A dog that has just relocated to your home will generally follow the rule of 3's. They typically take 3 days to feel comfortable with you, their new person, 3 weeks to begin to understand the rules and routines in your house, and 3 months to fully relax enough to allow their true personality to emerge. You must give them that time to adjust and decompress from previous life experiences before you start to build confidence and resilience around distractions.
Third, give them the skills they need to rely on by playing games and training away from distractions. Then add in distractions you can control in a manner that helps them to transition the skills from a learning phase to an automatic phase. Only then you begin to work around the distractions that you can not control. Until that time you must use management skills to keep both you and your dog safe, calm, and happy. This may mean tools such has a harness, gentle leader, and leash. But management also means choosing environments wisely for the best outcomes and setting up a daily routine that meets the dog's needs without exposing them to things that are dangerous or that they fear.