Version 21.0.1.119 (UDP3) Can not see the keyframe controls (like a down arrow to put keyframe here) in timeline for effects because message boxes for movies (movie 1, movie 2, ...) cover up the keyframe tools.
Windows has a tool called Snipping tool. click the Start button on the desktop - Windows Accessories - Snipping Tool, choose Window Snip to capture the full screen, save then post on here using the arrow button next to the smiley at the top of a new comment.
The location you are indicating in your image is not where the Keyframe controls and pane are.
For the Keyframe controls and pane to appear you must have an image or video object and an Effect selected that can be keyframed.
The image below shows the Size, Position effect from Movie Edit Pro 2021 - MEP 2022 is the same, the insert, delete, copy keyframe tools are indicated by the yellow arrow, if the pane is too small to see the keyframes, drag the border indicated by the green arrow to increase the height of the Keyframe pane.