Hai ghanshyam,
You can use PGadmin to see all the fields of any table. first just install the PGadmin app.

Connect the app with PSQL.

Server Group -->   Servers -->    localhost(localhost:5432) --> Databases --> <Data base name> --> Schemas --> public --> tables -->sale_order

Click the above table icon. and get the table.

Table fields depend on your modules be installed.

Thanks

Hi Ghanshyam,

If you wanted to get all fields of any object using script, you perform search for ir.model.fields with doamin [('model_id.model,'=',model_name)]