A Conditional Agreement is a sale and purchase agreement that has conditions that must be met before the sale is finalised. The buyer will usually put conditions in like getting a builder's report, having finance approved and reviewing the LIM or Record of Title, although a seller can also put in conditions.
If you have conditions in your offer, you will also have agreed to a date that you need to complete these tasks before - the seller can't wait around forever! Make sure that you have completed all of your to do's, including securing your lending, before this date so that you don't miss out on your home. If there are unforeseen delays you may be able to negotiate an extension through your solicitor, but it is much easier if you can avoid this by getting everything done on time.