Posting functions not working

We have been trying for the past 3 days to upload images to our media library and use them in or as a post. We have consistently been unable to do so. Nor can we access the media library when creating or editing a blog post. Same issue applies to adding a page to the website. Further, our SEO plugin is not reading from the post and we cannot add keyword tags. Finally, the break button that defines the amount of the post that is visible on the main blog page does not function. Featured image does not work either. We are extremely frustrated. Has anyone else experienced this problem? Can anyone tell us how to get these functions to work again? Thank you.