Google Translate is a fairly reliable way to get a Katakana version of your names that you can copy and paste into an online form. Click the audio icon under the Katakana to check that it's OK.
For the Kanji field, you could try typing your names as usual. If that fails, just paste in the Katakana version. (Alternatively, try double-width letters if you know how).
Good luck.


Google doesn't know that Cholmondeley is pronounced "Luxury Yacht," but it does a reasonable job with most names.