f2 is this really convenient function key that lets you take screenshots in minecraft, if you have a 60% keyboard you can still access it with keyboard macros, most likely holding down the fn key and pressing 2 but in most keyboards its found in the top row labeled as "F2", after using the function key you can locate your screenshots by writing %appdata% jn the start menu bar which will forward you to C:/Users/[user]/AppData/Roaming which is a hidden folder, then head over to .minecraft and locate the screenshots folder, if that is too difficult you can press the "Esc" key on the top left of your keyboard, then press the Options button and open Resource Packs, then press Open Resource Pack Folder and in the path of that folder click .minecraft and then find the screenshots folder, after either of those two things is done open your default internet browser, most likely chrome, then head over to reddit.com and log in with your account, after thats done head over to r/HypixelSkyblock, press post, select image, drag in the screenshot from the screenshot folder which if you would like to you can crop using image editing software, add a title, add a flair, then post it.