Hi @Vedika Bhosale,
Thank you for posting in Microsoft Q&A Forum.
From your description, could you kindly contact the owner of the shared file to check your permissions and confirm with us the permission on the file you are trying to download?
Because from the message you've shared, it saying that you don't have permission to download. Therefore, only the owner can change the permission to allow downloading.
The owner can follow these steps to grand your download permission:
1- Click on share > Manage access
2- In the Manage Access pop-up, find your account (or the group you belong to) and click on it.
3- Check the permission. If it says “Can’t download,” please change it to Can edit and apply the changes.
Thank you for your time, I'm looking forward to your response.
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