Begin by understanding that your private information (parents, etc) is confidential… meaning, no website should be able to give you that. What is trustworthy is your own personal documentation.. ie your birth certificate; your parents; grandparents, etc. Info on living persons should never be online.
Once you have worked from the PRESENT backwards.. and now have names/dates/places for (say) 8 of the gr grandparents, you can work to locate valid records on them. The 1930 census is open for research.. however, the one place with all census records is ancestry.com. It is not free.. it is worth the $$. You can get a great deal of info from those records (your library often offers it free to patrons).
Knowledge of HOW TO is free… but genealogy itself isn’t. It’s up to you as to how much you really think the knowledge is worth. My advice (many yrs experience) is to make the priority of research to be finding your ancestors, not necessarily websites, and not necessarily free.

Start with what your family knows as for certain (names, birth dates and places, marriage dates and place, death dates and places. Get all the siblings too where you know you have the right family. Go back as far as you can go. Then check out the following websites for HINTS. Don’t take any of it as right. Do your own research to PROVE it right or wrong. I have inadvertently put the wrong John to the right father. There were 2 sons named John but when the 1st John died as a baby they named the next son born John too. I put all th children of the 2nd John for the 1st John. Confusing, HUH? So get it right….

Try. If they can’t help you they have a list of other family history websites