table fields and text boxes in form not same

You need to specify the fields of the values you want to insert on your statement if you are not inserting values to all of them. Since you haven't provided the fields, it assumes that you want to insert to all of them, hence the error. An example of how to do it would be

INSERT INTO Table1 (column1, column2) VALUES ('value1','value2')

Also, the way you're constructing your query is dangerous, as its open to SQL injection attacks. Use SqlParameter[^] instead of concatenating values to your query.

Make a good practice of passing the fields and values in insert query like

insert into tablename (field1,field2,field3,.....,fieldn) values(value1,value2,value3,.....,valuen)

instead of using
//bad practice

insert into tablename values(value1,value2,value3,.....,valuen)

better to use procedure for insert query.

You need insert value into database use textbox text,

first you verified database table value fields datatype(int or float or char)

[osi_no] [int] IDENTITY(1,1) NOT NULL

, this is datatype is int.

so you could not insert textbox text because text for datatype is string,
so you convert to implicit or explicit.

example

+ int.Parse(txtOSITDSFromBank.Text) 

or

converto.Int32(txtOSITDSFromBank.Text)