You may take advantage of the HTML Wiki plugin for this: Wiki Markup and Plugins and then run a:
PUT call @ /v3/items/{itemId}/fields:
{ "fieldValues": [ { "fieldId": 80, "name": "Description", "value": "[{Html\r\n\r\n<b> This is some bold text with special charachter @@@###</b> <u> This is some underline text </u> <i> This is some italics text </i> <a href=\\\"https://www.google.com\\\">Visit google!</a> <p>RapidTables ™ </p> <p>RapidTables ® </p> <table style=\\\"width:100%\\\"> <tr> <th>Name:</th> <td>John</td> </tr> <tr> <th rowspan=\\\"2\\\">Telephone:</th> <td>55577854</td> </tr> <tr> <td>55577855</td> </tr> </table> <ul> <li>Coffee</li> <li>Tea</li> <li>Milk</li> </ul>\r\n}]", "type": "WikiTextFieldValue" } ] }