Algebra can be intimidating for many people. Many of us get the idea that we're "not good" at something and then we take that in as a part of our identity. Brad M. gave you a great strategy, and I can see how that could be very helpful. Part of what you need to work on changing, though, is how you consider yourself with regards to Algebra.
You say that "Algebra is very hard for me", which is a very definitive statement. It's framed in your mind in such a way that you are saying that it is the way it is and the way it will always be.
Try to reframe your mindset to something like: "I am having trouble with Algebra" or "I have had trouble with Algebra in the past". That way it isn't about you, it's about your situation. You can change your situation.
You're frustrated, and I can empathize with that. I've been where you are. Keep in mind, though, that you're obviously a smart person trying to do your best or you wouldn't be here. Anyone can learn to do anything with enough work and the right strategies. Algebra isn't very hard for you, algebra is something that you're working hard to understand. You'll find your way, and what will define you when you're done with this class isn't the difficulty of algebra, but the fact that you're a hard worker who can learn anything you set your mind to.
Now, that said, I have a particular challenge called dyscalculia. It's like dyslexia but with numbers. There is a related learning challenge called dysgraphia as well. I am fortunate that my case isn't a severe one, but it's bad enough that I know how you can understand a concept when it's taught and then have no idea how it works 15 minutes later. If this sounds like you, then you're going to have to work extra hard... but you can do it. I promise.
Also, if what I said in the previous paragraph sounds like your experience.... I don't know if you're in high school or college. If you're in high school then I recommend asking your parents or school counselor to look into dyscalculia. If you're in college then look into what learning resources your school has. They may be able to do an assessment for you to see if you have it. You can also Google search something like "strategies for dyscalculia students", much of what you'll find is meant for teachers, but you can adapt the strategies for yourself as well. (Things like doing assignments in chunks rather than all at once so you don't get overwhelmed, trying to use words rather than just letters, etc.)
Whether you have a particular learning challenge like dyscalculia (or something else) or you're just having a bit of trouble right now remember that it's temporary, it isn't part of who you are.
You can do this. I have faith in you.