I have recently received a printed pedigree chart of 20 pages.
My mother is included in the chart.
How/where do I start recording this information in Legacy?
How/where do I start to verify the information?
It covers England and Australia.
Your first decision should be to reverse the questions you have asked.
Do not enter unverified information into your new software tool, which ever one you choose.
Begin with your mother on the printed chart, select one claim (such as a birth date) and ask "How do they know that?" "Where is the evidence to support that statement?" When you are satisfied, then enter both the claim and the source of the evidence into your database. Then "rinse and repeat" as the shampoo advertisements used to say. When you have finished your mother, move on to your grandparents and examine each claim about them critically.
Knowing that only verified claims supported by evidence have been transferred over will give you an assurance that you are not simply typing unsupported junk in a race to get it all in the database. It also means that you now have a hobby for life, because family histories are never finished.
I agree with Fortiter, but with a few caveats, depending on whether your intended use of your database is as a "final report" or as the status of your work-in-progress. I avoid adding person records to my database without some verifiable source of the associated facts (although I admit to being less than 100% rigorous regarding what constitutes a "verifiable source"). I expect that most of us agree that an unsourced GEDCOM (or, in this case, a pedigree chart) can't be treated as a "source".
However, if the chart lists a person as b. 10 Nov 1887 to given parents in a given place, and the 1900 or 1901 census lists a matching child in a matching household, I would be OK listing the person with DOB "abt.10 Nov 1887" and including "unconfirmed" in the fact description until evidence for the specific date was discovered.
I find that it helps when, for example, I locate a source for a given place and time (e.g., church baptismal records), to easily be able to identify all the persons in my database who MIGHT appear in that source. Including a certain amount of clearly-identified speculation in the database helps in that regard. This may not be an issue if your database is, say, 1000 persons or less, but becomes more of a management problem with higher orders of magnitude.
I agree with Fortiter that your best option is to verify the data as your enter it, but my alternate suggestion is that you may want to enter and first mark as speculative, then verify, rather than verify, then enter (so long as the entry stops with the first speculation).
Again, this depends on whether you use your database to help organize your research, or whether you have a separate system for organizing your research before entering into your database.
Legacy family tree software has a number of training CDs and videos that will help you get started with the program. Several of them are free; see this link.