ていかなきゃならん事 and にゃ

Question

I have the following sentence:

A: まあ、さっさと忘れろ。お前にゃこれから先、覚えていかなきゃならん事が山ほどできるんだし。

Context: A and B were involved in a sparing session, and after winning B exclaims they will cherish this memory forever. A responds like above.

The first weird bit, which I don't think is a language problem, but there might be some nuance I'm missing is that:

まあ、さっさと忘れろ = Now now, forget this quickly.

Which is a strange thing to command someone to do. But eh.

The main meat of this question is the later bit. Now this is colloquial, but not that heavy, and can be expanded back into regulation Japanese as:

A: お前にゃこれから先、覚えていかなきゃならん事が山ほどできるんだし。

A: お前にはこれから先、覚えていかなければならない事が山ほどできるのだし。

The first bit にゃ=には, I'm not 100% sure. I mean I know that (for) or ねば (if) are options, and I can't really see if working off just you, buut, not sure. In any case the bit up to the comma is

From now on you

The next bit is my stumbling block. The 覚えていかなければならない事 bit. The verb itself probably means "have/should/must continue to remember" The interpretation would depend on what that 事 is doing here. Is it nominalizer? If so the sentence is strange: "Being able to having to continue remembering many."

I think it's probably here as a noun, meaning an event or something to be memorized. So it's "things/events you have to continue memorizing". Have due to なければならない and continue due to ていく.

Mating that with 山ほどできるのだし。is still weird though. の is there to nominalize the previous bit, だ is there to make it a statement and し is likely there to denote this as one of reasons for forgetting this fight.

But still "From now on, you will be able to have to continue memorizing many things." I'm assuming we are supposed to figure out that できる refers to the ability to memorize, all these things that can't be forgotten?

So the final statement would be:

A: Now now, better forget this quickly. (If you do so)? from now on, you'll be able to memorize many more events/things that you must not forget.

Buut I don't think I really got the nuance of this one.

So basically, how far am I off, and where am I making a mistake here?

In particular,

1. Is にゃ ねば or には?

2. What is the meaning of The 覚えていかなければならない事

3. And how does the previous fit with 山ほどできる

Answer 1

1. にゃ in this case is には. (After the 未然形/pre-nai-form of a verb, にゃ can be ねば; "行かにゃ" = "行かねば").
2. This 事 is not a nominalizer but a plain noun meaning "things".
3. This できる is a simple intransitive verb meaning "to form" or "to be made." It does not have a potential meaning.

Put together, 覚えていかなきゃならん事が山ほどできる ≒ 覚えていくべき事が山ほどできる ≒ "lots of things to remember will form" ≒ "there will be lots of things you need to learn/remember (over the course of time)."

I don't think this sentence means the listener will keep encountering memorable "events". The sentence says his memory must be consumed for more meaningful subjects.