You can apply for a Divorce on your own or through a lawyer in Singapore.
The choice is completely yours.
If you want to and can represent yourself in the Divorce proceedings, the Court will allow you to do so.
However, you will need to comply with the legal, procedural and formal requirements of conducting Court proceedings, such as ensuring that the documents you file in Court are in the correct format.
If you choose to represent yourself, the Family Court cannot give you any advice on what you should say or do.
If feel that it is safer to receive advice on what you should say or do in your Divorce case or the strengths and weaknesses of your case, you should get advice from a qualified lawyer.