Con el tiempo, quiero dejar atrás mi miedo y hablar en público con más confianza.

Con el tiempo means with time / over time / in time. It suggests a gradual process, not a sudden result.

In this sentence, it implies:

• As time passes, I want to...
• Over time, I want to...

It is similar to eventually in some contexts, but not exactly the same:

• con el tiempo = emphasis on gradual change
• eventually = emphasis on the final result

So here, con el tiempo fits better because the speaker is talking about personal progress.

In Spanish, after a conjugated verb like quiero, you can add one or more infinitives if the same subject is doing all the actions.

So:

• Quiero dejar atrás mi miedo y hablar en público... means
• I want to leave my fear behind and speak in public...

You do not need to repeat quiero because both dejar atrás and hablar depend on it.

You could repeat it:

• Quiero dejar atrás mi miedo y quiero hablar en público but it sounds more repetitive and less natural here.

Literally, dejar atrás means to leave behind.

Idiomatic meanings include:

• to move on from something
• to overcome something
• to stop being held back by something

In this sentence, dejar atrás mi miedo means:

• to leave my fear behind
• to get past my fear
• to overcome my fear

It is a very natural expression in Spanish for emotional or psychological progress.

Mi miedo means my fear, so it makes the fear clearly personal.

Spanish often uses possessives like mi, tu, su when talking about emotions, feelings, or personal experiences:

• mi miedo
• mi inseguridad
• mis dudas

If you said dejar atrás el miedo, that would usually sound more general:

• to leave fear behind
• fear as a concept, not specifically my own fear

Here, mi miedo is more natural because the speaker is talking about their personal fear.

Hablar en público is the standard expression for to speak in public / to do public speaking.

It focuses on the situation:

• speaking before other people
• speaking openly in front of an audience

By contrast, hablar al público means to speak to the audience / to address the public. That can be correct in other contexts, but it is less about the general skill of public speaking.

Compare:

• Me da miedo hablar en público. = I’m afraid of speaking in public.
• El presidente habló al público. = The president spoke to the public.

So in your sentence, hablar en público is exactly the right choice.

It literally means with more confidence, but in natural English it often translates as more confidently.

So:

• hablar en público con más confianza can mean
• to speak in public with more confidence or
• to speak in public more confidently

Spanish often uses con + noun where English might prefer an adverb:

• con calma = calmly
• con cuidado = carefully
• con seguridad = confidently / with confidence

Both English translations are fine here.

Spanish often uses más even when the comparison is only implied.

Here, the implied meaning is:

• more confidence than I have now

So con más confianza means:

• with greater confidence
• more confidently than before

This is very common in Spanish. The comparison does not need to be fully spelled out if it is obvious from context.

Yes, but the meaning changes slightly.

• Hablar en público con más confianza focuses on how you want to speak.
• Tener más confianza focuses on the internal feeling of confidence itself.

For example:

• Quiero hablar en público con más confianza.
  = I want to speak in public more confidently.
• Quiero tener más confianza al hablar en público.
  = I want to feel more confident when speaking in public.

Both are natural, but your original sentence is more action-focused.

The comma is used because Con el tiempo is an introductory phrase placed at the beginning of the sentence.

This is common in Spanish:

• En general, ...
• Por suerte, ...
• Con el tiempo, ...

The comma helps separate the introductory idea from the main clause:

• Con el tiempo, quiero dejar atrás mi miedo...

In informal writing, some people may omit such commas, but using it here is standard and clear.

Yes, it sounds natural in Spain.

It is clear, correct, and idiomatic. A speaker from Spain might also say similar versions such as:

• Con el tiempo, quiero superar mi miedo y hablar en público con más seguridad.
• Quiero ir dejando atrás mi miedo y ganar confianza al hablar en público.

But your original sentence is completely natural and appropriate in European Spanish.

Both can work, but they are slightly different.

• confianza = confidence, self-confidence, trust in yourself
• seguridad = assurance, self-assurance, sense of certainty

In speaking contexts:

• hablar con más confianza sounds personal and emotional
• hablar con más seguridad sounds a bit more like speaking firmly or with assurance

So:

• con más confianza = more self-confident
• con más seguridad = more assured / more secure in delivery

Your sentence with confianza is a very good choice if the focus is overcoming fear.

Yes. Dejar atrás is very flexible and often used with:

• fears
• problems
• bad experiences
• old habits
• stages of life

Examples:

• Quiero dejar atrás mis inseguridades.
• Por fin dejó atrás una época difícil.
• Necesito dejar atrás el pasado.

So using it with mi miedo is completely natural and very common.