Thanks for reaching out. That topic can be confusing. I’d love to help you figure it out.
What format do the presets come in the packages you have bought, XMP, Lrtemplate, or DNG? If they are in a compressed folder (.zip, rar, etc.), you can use a 3rd party software to unzip them so that Lightroom can read the supported file formats on iPad or iPhone.
If you have access to the Adobe Lightroom desktop, you can import presets on the Lightroom desktop, and it will sync over to your Phone shortly. If you are only using Lightroom mobile, you can check the responses on this community thread: https://community.adobe.com/t5/lightroom-ecosystem-cloud-based-discussions/import-dng-presets-in-lig...
Let us know if this helps,