how to get file address?

You will have data loss if you change the field type. They store their files in different locations entirely.

1- Is it possible to manually change the names of the files and move the uploaded file to the correct storage location to show as image?
2- I want to have several image fields. I don't want to use the image field to store the user's avatar, but I want to use it for some of his scanned academic documents. Do you see a problem with this? For example, I realized that the allowed dimensions should not be small

1- Is it possible to manually change the names of the files and move the uploaded file to the correct storage location to show as image?

Yes, all CB files are stored in /images/comprofiler. Review the structure there carefully.

2- I want to have several image fields. I don't want to use the image field to store the user's avatar, but I want to use it for some of his scanned academic documents. Do you see a problem with this? For example, I realized that the allowed dimensions should not be small

I suggest using CB Gallery then, but sure you can have as many image fields as you need and each can have their own sizing limits.

i study cb primer book and search in this forum and find this  but it can not show modal in the cb backend. i can understand i can create a copy of aaaa.jpg image and rename that witht tnaaaa.jpg and move them to /public_html/images/comprofiler/ path and then change the cb file field to image field and it work correclty . but i need administrator can click on the image and open a popup to can review that image and if it has some situation then approve that user. is it possible popup image field in the profile of user in the backend?
(i can not use CB Workflows, it doesn't have a good ux and can not show the image field in first view of CB Workflows list)

Image fields can have approval. Simple enable it in that image field. The normal frontend image approval page allows approving/rejecting custom image fields as well. There is no popup functionality in image fields.

(i can not use CB Workflows, it doesn't have a good ux and can not show the image field in first view of CB Workflows list)

Not sure I understand the problem with CB Workflows. You don't have to use it though. You can reach the image approval page without it. Regardless CB is open source. Change it to fit whatever your needs are. Reuse the approval endpoints and implement your own PHP rendering if that's what you want to do or just restyle it with CSS.