I have prepared entries in a journal but when I transfer the figures over to the trial balance sheet the numbers are way off and don't balance. I don't know how to figure out what I have done wrong. Where do I start?

First I would check to make sure you posted your debits and your credits into the proper columns in the trial Balance. If you did then I would check my Account balances.

Another thing to do is check your journal entries. Did you post the transaction properly such as a Debit to an Asset or Exense account increased the account while a Credit to the Liability, Equity, or Revenue account increased the account while a Credit to the Asset or Expense account and a Debit to a Liability, Equity, or Revenue account Decreases the account.

Did you post the Transaction to the proper accounts.

Purchase furniture rs.2000 in cash - what is the journal

Debit Furniture or Plant, Property, & Equipment - Furniture for the amount (Use whatever Asset Account for furniture that you have)
Credit Cash for the amount