Hi @Zoey Liang,
Thank you for posting in this community.
Question1: upload files from onedrive.
- Open OneDrive from Website.
- Go to My Files->select files which you want to upload.
- Copy to->select site and library where you what to upload files. Click copy here.
- Here is result:
You can also use power automate to upload files from OneDrive to SharePoint sites. Here is the reference: Copy Files from OneDrive to SharePoint: 4 Quick Methods
Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please make sure that you completely understand the risk before retrieving any suggestions from the above link.
Question2: upload files from other sites.
In SharePoint Online, you can copy files to other sites.
- Select the file which you want to upload ->Copy to.
- Select the place where you want to upload and click copy here.
- For more information about copying files in SharePoint, please check out this article: Move or copy files in SharePoint
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.