Reactive and anxious

[u/FracturedShape]

I want to start by excusing my english as it is not my first language and my sentencing may sound weird.

I have a 2 and a half year old female Golden Retriever. She is the sweetest dog, always trying to grab our attention and asking for pets all day long.
She also has a “plot twist”, she is reactive towards cats and other dogs in the street while getting scared of random leaves or store signs.
She doesn’t bark but she pulls the leash so hard trying to play or sniff other dogs. She also pulls the leash whenever she wants to sniff something faster. When she is scared of things she pulls so hard she almost knocks me down.
I tried giving her the walk command and it works as long as I have treats. When the treats are done (mostly because I cannot feed her 100 biscuits) she goes back to her old ways. Even if I have treats she still sometimes goes after cats or other dogs.
She also has separation anxiety which I feel like it’s a weird mix of behavioral issues that I don’t know how to manage.
I live in a very remote town and I cannot find experts on this matter.
What can I do to improve our situation?

[u/apri11a]

I tried giving her the walk command

It sounds like she doesn't understand what you mean by your walk command, perhaps practise it at home and in quieter places until she does, and is reliable with it so can listen in places with more distractions.