The full form of JP depends on the context. It can stand for several things.
JP as Justice of the Peace
According to the Britannica Dictionary, JP stands for justice of the peace. This is a judicial officer appointed by government to administer oaths, perform certain marriage ceremonies, and conduct preliminary investigations in criminal cases. Examples of JP's work can be found on sites such as the Harris County Justice of the Peace Courts website (http://www.jp.hctx.net/). Collins English Dictionary also confirms this definition (https://www.collinsdictionary.com/dictionary/english/jp).
JP as J.P. Morgan
In the financial world, JP frequently refers to J.P. Morgan, a prominent American financier and investment banker. The name is associated with the major financial institution, JPMorgan Chase & Co. (https://www.jpmorganchase.com/about/our-history). Information about J.P. Morgan himself is readily available on Wikipedia (https://en.wikipedia.org/wiki/J._P._Morgan). Many subsidiary companies and services also use the JP abbreviation, such as J.P. Morgan Asset Management (https://am.jpmorgan.com/us/en/asset-management/adv/resources/account-servicing/) and J.P. Morgan Securities LLC (https://secure.chasecdn.com/content/services/structured-document/document.en.pdf/dao/form-crs-jp-morgan-securities.pdf).
JP as Jet Propulsion
Another less common meaning, as cited by Dictionary.com (https://www.dictionary.com/browse/jp), is jet propulsion. This refers to the propulsion of aircraft or spacecraft using jet engines.
In summary, the full form of JP depends heavily on the context in which it is used. The most common meanings are Justice of the Peace and J.P. Morgan (referring to the company and its subsidiaries).
