how do I build up my family tree ?

Same way as anyone does, you start with yourself and the records you already have at home and prove your ancestry from yourself, researching and proving back one generation at a time http://familytimeline.webs.com/recordsinyourownhome.htm always remembering to prove each person or they do not go in your tree bearing in mind one wrong person in your tree means you are no longer researching your ancestors

You have your birth certificate? It has the names of both of your parents including your mother's maiden name. How about your parents and grandparents? Do they have theirs? Also death certificate usually have the names of both parents of the deceased including mother's maiden name. If your family is in the U.S., you will get back to the time before births and deaths were recorded, then there are church records, census records, Find out what living family has. Maybe they have some birth, marriage and death records on your ancestors. Maybe they have some baptismal, confirmation, marriage certificates from your ancestors churches. Maybe they have some old family bibles, old family photos, old wills, and other records.

Once you have done this go to a Family History Center at a Latter Day Saints (Mormon) Church. They have records on people all over the world, not just Mormons. If you find anything in their database you would like to view and print off a copy of an original document, they can order microfilm for you to use there for about $5. I have never had them to try and convert me nor have I heard of them doing that to anyone else that has used their resources. Just use the following link to find the nearest Mormon FHC.

https://familysearch.org/locations/centerlocator

Use t the internet as a tool only and never never accept what you see in someone else's family tree as fact until it is verified with an actual records. The trees are submitted by the subscribers and no, the websites do not verify what their subscribers submit. It would be far too costly. Even when you see the absolute same information on the same people from many different subscribers that doesn't mean it is accurate as too many dingies copy without verifying. Some websites such as Ancestry.Com and FamilySearch.org have both records and family trees. Distinguish the difference. Family trees on their websites are not records.

Have more children.

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