Warm mMemories

In being anxietyous about my future i, I forgot about my past.

OR: forget

I remember a little from my childhood, and most only because somebody reminded me of those events.

My attitude toward the past is warm.

Memories of those days still warm the soul.

OR: my soul

It is a pity that there are a few of them.

InWhile being anxietyous about my future i, I forgot my past.

we usually talk about our feelings as adjectives, not being "inside" a feeling

either the/my future, we can't just say it alone

I remember a little from my childhood, and mostly only because somebody reminded me of ithose events.

Original is correct but this sounds better since you're talking about your childhood already, you can just say "it"

My attitude towards the past is warm.

Better to say "I feel warm about the past."

Memories of those days still warm themy soul.

Original is okay but this is better to be consistent

It is a pity that there are only a few of them.

original is still okay but best to be specific

In anxietymy fear about the future iI forgot my past.

the: we usually talk about "the future", "the present" and "the past"

I remember a little from my childhood and mostly only because somebody reminded me of those events.

My attitude to the past is warm.

Alternative:
I have fond memories of my past.

Memories of those days still warm themy soul.