I have always believed in magic my inter life. I see energy and I hear high pitches noises. I found out I'm a witch by blood from my grandma but everytime I cast a spell it doesn't work I've read articles and forums. Do I haft to have a altar to cast spells or do I need it to give my spells a stronger affect
You do not have to have an alter to cast spells. If you are completely new (whether if you are one by blood or not) saying some words and mixing ingredients together won't do anything. You need to put your intent into a spell and raise energy for a spell. Also, the spell may have not worked just yet, spells take time and they could take as long as years to take effect so it more than likely won't happen the very next day. You also are not specific on what spell you are casting so you could get further help with it.
There is no right or wrong way to practice magic. One does not necessarily need an altar. It's all about preference. I personally don't have an altar and all of my workings come out great. Some people have an altar, while others don't.
Echo, my grandmother was also a practitioner of witchcraft, I found out. But she might not have called it that. She lived in the Appalachians, where she met my grandfather. It wasn't until recently -- years since her death -- that my sister is telling me things that I was not allowed to know as a kid, and things that make sense considering things I encountered at her house, and things she used to say.
It does not necessarily make one more or less likely to be able to do magic or witchcraft. But it can be very interesting to encounter and research!'
Considering your profile says you live in West Virginia, it is possibly your grandmother practiced some of the widespread and often varied forms of folk magic, conjure, and aspects of Hoodoo, found among older generations of hillfolk.
Learning these specific traditions can be very difficult, considering very few were willing to have their beliefs recorded, preferring to pass knowledge to those they deemed both willing to learn, and most likely to respect the tradition. But there is hope.
For example, the Foxfire Book series is a long set of magazine articles, covering the dying culture of the older generations of the Southeast and Appalachian US in the 60s. It not only mentions the way people lived, including some very matter-of-fact coverage of gruesome aspects of day-to-day life (namely preparing slaughtered livestock for various meals), but also some folk traditions. There are some other books on the specific topic as well, though titles escape me at the moment.