Welcome to the forum!
Good news is that this issue is pretty common and can be worked on and addressed!
First half of the solution for now is managing/supervising in some way to help prevent your dog from eating these things. It might mean a leash for the time being. Not used for leash pops or corrections though. Just to keep your dog with you so she cannot run off and find these tasty things.
Ditto training ''leave it.''
I start sitting with food in hand, and back of hand glued to my knee. I ignore any licking, pawing, and other attempts to get the food. When my dog makes the choice to back off I open my hand. If my dog tries to steal the food, fist closes and I wait. If my dog remains polite, I pick up a treat with my free hand and give it to my dog. I continue to reward as long as my dog is polite. Fist closes any time my dog gets pushy and tries to take a treat.
Then I work on this is other contexts...
Distractions on tables and chairs, plate or bowl in my lap, distraction on floor, etc.
Again covering if the dog tries to steal and uncover and then reward if polite. If the item is on the floor, I cove with my foot.
I also work with different distractions...
Different foods, toys, paper, bags, etc. If a non-food item I reward most of the time with treats or a toy from my pocket.
Not matter what the distraction is, I strive to make sure my dogs never actually get it on their own. If I want them to have it, I pick it up and give it to them.
There are some other drop or leave it games and methods in this thread including videos. The "It's yer choice" video shows what I described above and some some of the different ways you can progress. https://www.dogforum.com/training-beh...lmness-168218/
Also agree with working on attention and walking with you will help a ton. Recall away from distractions as well! There are many methods to teach these skills. Lots in these threads. https://www.dogforum.com/training-beh...-walking-1683/ https://www.dogforum.com/training-beh...s/recall-9595/