Con ayuda de mi profesora, ya no tengo miedo de hablar en clase.

Con ayuda de means with the help of.

Both con ayuda de and con la ayuda de are possible in Spanish. The version in your sentence sounds very natural and slightly lighter or more idiomatic in everyday speech.

• Con ayuda de mi profesora = with the help of my teacher
• Con la ayuda de mi profesora = with the help of my teacher

The meaning is basically the same here. Spanish often drops the article in fixed expressions like this.

In modern standard Spanish, possessives like mi, tu, su, nuestro usually go directly before the noun:

• mi profesora
• tu libro
• su casa

So mi profesora is the normal way to say my teacher.

A structure like la profesora mía does exist, but it is used differently, usually for emphasis, contrast, or clarification:

• Mi profesora = my teacher
• La profesora mía = my teacher / that teacher of mine

For a neutral sentence, mi profesora is the right choice.

Ya no means no longer, not anymore, or not any longer.

So:

• Ya no tengo miedo = I’m not afraid anymore / I no longer feel afraid

This is a very common Spanish pattern:

• ya no + verb

Examples:

• Ya no vivo allí. = I don’t live there anymore.
• Ya no estudio francés. = I don’t study French anymore.

It shows that something used to be true before, but now it isn’t.

In Spanish, the normal expression is tener miedo = to be afraid / to feel fear.

So Spanish says:

• Tengo miedo = I’m afraid

Not:

• soy miedo
• estoy miedo

This is just one of those cases where Spanish uses a different structure from English. English uses to be; Spanish uses to have.

Other similar expressions:

• tener hambre = to be hungry
• tener sed = to be thirsty
• tener sueño = to be sleepy

Because miedo normally takes de before a noun or an infinitive.

So:

• tener miedo de algo = to be afraid of something
• tener miedo de hacer algo = to be afraid of doing something

Examples:

• Tengo miedo de los perros. = I’m afraid of dogs.
• Tiene miedo de conducir. = He/She is afraid of driving.

That is why de hablar is correct: miedo de hablar = fear of speaking.

After tener miedo de, Spanish normally uses the infinitive to talk about an action in general.

• tener miedo de hablar = to be afraid of speaking

The infinitive in Spanish often works like the -ing form in English after certain expressions.

Compare:

• English: I’m afraid of speaking
• Spanish: Tengo miedo de hablar

So even though English uses speaking, Spanish uses the infinitive hablar.

En clase usually means in class or during class in a general sense.

• hablar en clase = to speak in class

Spanish often leaves out the article in common expressions involving places or activities when speaking generally.

Compare:

• Estoy en clase. = I’m in class.
• Hablamos en clase. = We speak in class.

If you say en la clase, it can sound more specific, like in the classroom or in that particular class. In this sentence, en clase is the most natural choice.

The phrase Con ayuda de mi profesora is an introductory phrase at the beginning of the sentence. In writing, Spanish often uses a comma after this kind of opening element:

• Con ayuda de mi profesora, ya no tengo miedo de hablar en clase.

The comma helps the sentence read more clearly. In a short sentence like this, some writers might omit it, but using it is completely natural and correct.

Yes. That is also a very natural sentence.

• Ya no tengo miedo de hablar en clase.
• Ya no me da miedo hablar en clase.

Both mean roughly the same thing: I’m not afraid of speaking in class anymore.

The difference is mainly in structure:

• tener miedo de = to have fear of
• dar miedo = to give fear / to be scary or frightening to someone

So:

• Me da miedo hablar en clase = Speaking in class scares me
• Tengo miedo de hablar en clase = I’m afraid of speaking in class

Both are common.

The structure is:

• Con ayuda de mi profesora = introductory prepositional phrase
• ya no tengo miedo = main clause
• de hablar en clase = complement explaining what the fear is about

So the sentence breaks down like this:

Con ayuda de mi profesora,
with the help of my teacher,

ya no tengo miedo
I’m no longer afraid

de hablar en clase.
of speaking in class.

This is a very useful pattern to learn:

• Con ayuda de X, ya no tengo miedo de + infinitive

Example:

• Con ayuda de mis amigos, ya no tengo miedo de conducir.
  With the help of my friends, I’m no longer afraid of driving.

You would say mi profesor instead of mi profesora.

So:

• Con ayuda de mi profesora... = with the help of my female teacher...
• Con ayuda de mi profesor... = with the help of my male teacher...

Everything else in the sentence stays the same:

• Con ayuda de mi profesor, ya no tengo miedo de hablar en clase.