Transform flat xml to another xml using XSTL

I want to learn XSTL but i can't fine a good online full course. I need to transform this XML using XSTL:

<product version_id="FullPro">
<metadata>
<element name="D1" index="event_id" />
<element name="D2" index="event_id" />
</metadata>
<LLL-info S_id="10778" T_code="N5" SS_id="50" S_Path="\TMP" />
  <File-info F_id="10778" F_path="\D\TMP.xml" />
</product>

My output XML should look like this:

<InI>
    <GeneralData>
        <PType>D1</PType>
        <PType>D2</PType>
    </GeneralData>
    <StorageData>
        <StorageId>10778</StorageId>
        <StorageCode>N5</StorageCode>
        <SStorageID>50</SStorageID>
        <StpragePath>\TMP</StpragePath>
    </StorageData>
    <Files>
        <File>
            <FileID>4</FileID>
            <RelativePath>\D\TMP.xml</RelativePath>
        </File>
    </Files>
</InI>

Please help.