need pay, need to pay

[e2e4]

/A learner/

That tells me how much attention I need pay to any further submissions from you.

Do we need "need to pay" in the sentence instead of "need pay"?

I reckon so.

[Johnson_F]

/That tells me how much attention I need pay to any further submissions from you.

Do we need "need to pay" in the sentence instead of "need pay"?

No.
'Need' can function as a modal verb, in which case 'to' is not needed.
In can also function as a full verb, in which case it is necessary to use 'to'.

[e2e4]

Is, from a different point of view, "need pay" the present subjunctive as well?
(A deliberative one?)

[Johnson_F]

Is, from a different point of view, "need pay" the present subjunctive as well?

It could be argued that 'need' in 'I doubt if he need pay' is subjunctive, though there is little point in so doing - modal verbs do not have a distinctively subjunctive form.

If a person, using the non-modal 'need' were to say, 'I doubt if he need to come,' then it would be a present subjunctive form.