"At a stone's throw" means-

• "At a stone's throw" means- খ) At a short distance

• A stone's throw
- English Meaning: A very short distance.
- Bangla Meaning: একেবারে কাছে; সন্নিকটে; খুব অল্প দূরত্ব।

• Ex. Sentence: She lives just a stone's throw away from the beach.
- Bangla Meaning: সে সমুদ্রের পাড় থেকে একেবারে কাছেই থাকে।

Source:
1. Oxford Dictionary.
2. Merriam-Webster Dictionary.