I personally got rid of OneDrive by uninstalling it and I have never encountered any issues with my sims files since then.
You can also just disable OneDrive so your downloaded files won't end up in there. If it is there, there's an option in OneDrive to download files, so do that and transfer the file to the WickedWhims folder inside your Mods folder.
3) When you download WickedWhims, the folder is zipped, so if you are using a Windows computer (some newer computers don't need this so you can skip if your computer can automatically extract/unzip them), you would need to extract/unzip the folder using a file archiver and the unzipped folder is what you should place inside your Mods folder. I believe some Macs come with built in file archivers, hence, there is no need to do this step, but if you don't see that feature, go ahead and search Google for a free file archiver that is compatible with your MacOS Ĥ) If one of the Wicked Whims files is missing, look into other locations in your computer such as OneDrive.