The acronym UBO means Ultimate Beneficial Owner (‘bénéficiaire effectif’ in French) within the meaning of the law of 11/01/1993.
The ultimate beneficiary of a legal entity is the natural person who, acting alone or in conjunction with others, directly or indirectly, in law or in fact, is responsible for the ultimate control of the company. The term “control” is here to be understood as the fact of holding the authority, in law or in fact, necessary to exercise a decisive influence over the appointment of a majority of the directors or officers of a business or over the way in which the business is managed.
There are three types of ultimate beneficiary:

1) Directors holding a formal office from the Board of Directors such as the CEO, the CFO or the treasury manager, and “deputy” corporate officers in the general sense.

2) Shareholders (natural persons) who own or control (directly or indirectly) at least 25% of the business, or who hold at least 25% of the voting rights.

3) Natural persons who do not match the definition in points 1 and 2, but who exercise a decisive influence on appointments or on the running of the business.

Note:
If you are independent and the sole shareholder, please simply give your own details.