Hi Nitzanch,
For the text, we could add the notes as below:
1.Tap the first word you want to highlight and then drag the selection handle to the end of the text you want to highlight. If you're adding a note, select the text that the note is about. (If you're using a mouse, drag over the text to select it.)
2. Tap or right-click within the selected text, and then tap or click Highlight or Add a note.
Note
You can highlight text and add notes only if the author has granted permission to do so. To check this, swipe up from the bottom edge or right-click within the app, tap or click More, and then tap or click Info. Under Permissions, see if Add notes and highlight
is selected. If it's not selected, you can't highlight text or add notes.
For the pictures, I am afraid it is not available to add a note. It is by design. You may consider to use the other softwares to achieve this.
Best r