例文1）この本は私には難しすぎると思う
例文2）この本は理解できそうにない
例文3）この本は私のレベル（理解力、英語力、など状況に応じたニュアンスで）を超えている
文字通り訳すと、
I don't think I can read the book because it is too difficult.
ですが、"because" などを使うと文章がやや硬くなるので、この程度にさらっと言うのが自然だと思います。
また、『〜気がしない』のニュアンスは"think" で表しています。
I don't think I can read this difficult of a book yet.
I don't think I am ready for this book yet.
This book is a little too hard for me right now.
I don't think I can read this difficult of a book yet.
Can you suggest an easier book for me? This one is too difficult right now.
I can't read this book so can you suggest an easier one for me?
My English isn't good enough to read this book but I would be interested in an easier one.
If you add "yet" or "right now" it gives the listener the idea that you could be ready for the book in the future so an easier book can be suggested. Also asking for something else will make the teacher feel that you want to read but just need something easier.
I don't think I am ready for this book yet.
（この本はまだ私には読めないと思います）
This book is a little too hard for me right now.
（この本はまだ私にはちょっと難しすぎます）
I don't think I can read this difficult of a book yet.
（まだこんなに難しい本は読めないと思います）
Can you suggest an easier book for me? This one is too difficult right now.
（もう少し易しい本はありますか。この本はまだ難しすぎます）
I can't read this book so can you suggest an easier one for me?
（この本は読めません。もう少し易しいものはありますか）
My English isn't good enough to read this book but I would be interested in an easier one.
（私の英語力ではこの本は読めません。でも、もっと易しい本があれば教えて欲しいです）
"yet" または "right now" を加えると、将来は読めるようになるかもしれないというニュアンスになります。ですから、相手はより簡単な本を薦めることができます。
また、「他の本はありますか」と聞けば、本を読みたい気持ちはあることが伝わります。
"I think i will struggle to read this"
To 'struggle' with something is referring to having difficulty with something, in this context it is explaining that they have difficulty withing reading something.
"This book might be above my level"
For something to be 'above my level' is often a term used when something is difficult and that you cannot understand yet, something that you will need more research/study in.
"I think I will struggle to read this"（これを読むのはなかなか難しそう）
'struggle' は「～に苦労する」という意味です。ここでは、「読む」のに苦労すると言っています。
"This book might be above my level"（この本は自分のレベルを超えているかもしれない）
'above my level' は、難しくて今はまだ理解できない事を表すときに使われます、さらなる調査／勉強を必要とする事です。
I do not think I am going to read this book because it is to difficult.
▪ I do not think I am going to read this book because it is too difficult.
To say "I do not think I am going to read this book" is saying that you already started giving up on reading the book.
It also means that you have lost some interest in the book.
"because" is you giving your reason why you are not going to read the book.
"too difficult" means that it is not easy and you are not going to understand it.
This sentence indicates that you have lost interest in this book because it looks too difficult to read and you do not want to read it anymore
【例】
▪ I do not think I am going to read this book because it is too difficult.
（この本は難しすぎるので読む気がしません）
"I do not think I am going to read this book" とは、その本を読むことをすでにあきらめている、と言う事を言い表しています。
また、これは読む気がしない、と言う事も意味しています。
"because"とは、何故その本を読まないかと言う理由を説明しています。
"too difficult"とは、簡単ではない、理解が出来ないという意味になります。
この表現は、その本が難しすぎるので読む気がしないのでそれ以上読みたくない、
と言う事を言い表しています。
This book seems like it would be too difficult for me to read
I don't think I could read this book. It looks like it might be difficult.
When you want to express that a certain book seems difficult and that you don't think you can read it; then you can say this in the following ways:
-This book seems like it would be too difficult for me to read
-I don't think I could read this book. It looks like it might be difficult.
その本が難しくて読めそうにないなら、それは次のように説明できます。
-This book seems like it would be too difficult for me to read（この本は自分には難しくて読めそうにない）
-I don't think I could read this book. It looks like it might be difficult.（この本は自分には読めないと思う。難しそうだから）
If something is not easy to do then we can say that it is 'difficult' or 'hard' to do
If you are learning or new to a language then you might say it's 'above your level' meaning you are not at a point where you understand this yet
When explaining that the book you are reading is hard for you to another person, use these phrases:
1. "I find it challenging reading this book."
Challenging - To test your knowledge/ability
This word can be used instead of difficult.
2. "This book is hard for me to read."
This describes that it is hard for you to read. Which means you may misunderstand the words or the way words are pronounced.
3. "This book is difficult for me to read."
Similar to the previous examples, yet difficult has replaced the words 'hard' and 'challenging'.
読んでいる本が難しいことを説明したいなら、以下のフレーズが使えます。
1. "I find it challenging reading this book."（この本は難しいです）
Challenging - 知識／能力が試される
この単語は 'difficult'（難しい）の代わりに使えます。
2. "This book is hard for me to read."（この本は難しいです）
ここでは「読むのが難しい」と言っています。つまり、意味あるいは発音の難しい単語があるということ。
3. "This book is difficult for me to read."（この本は難しいです）
上の二つの例と似ていますが、ここでは 'hard' あるいは 'challenging' の代わりに 'difficult' を使っています。
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