Learn English – use “will” with “have to”

This is fine. The present > future pattern is 'usual' only in conditional constructions:

If he does this, I will do that.

In these the 'tense' forms aren't really time references. I will do isn't any more futurive than the does - it signifies subsequence or consequence relative to the if clause rather than an actual temporal relationship to the time of utterance.

In other contexts, the restrictions on using future constructions in consecutive clauses are logical and factual, not grammatical. All of these are OK:

He will do this and I will do that.
He will do this to insure that I will do that.
He will do this, consequently I will do that.

As for the question TecBrat raises:
In your first sentence, the can is only 'present' tense in form; its reference is just as futurive as the will in your second sentence. The fact is, English doesn't have a 'present' form, despite the name. The two tenses in English verb forms are not past and present but past and non-past, and the 'present' form can be used with either present or future reference.

I'm in your neighbourhood tomorrow evening—want to get together for a drink?

When you get right down to it, this is the only way to express future reference with can. Full modal verbs like can cannot be used with auxiliaries like will and be and have, because they are defective—they do not have the non-finite forms (infinitive and participles) which the auxiliaries require.

BE + going to - Lindsay is going to fly to New York next week.

Forms with BE + going to possibly originated in such utterances as:

1. We are going to meet Andrea at the cinema,

uttered when we were literally going, i.e. on the way, to the meeting. At the moment of speaking there was present evidence of the future meeting. This use has become extended to embrace any action for which there is present evidence – things do not have to be literally moving. Consider now these two utterances:

2. Look at those black clouds. It's going to rain.
3. Luke is going to see Bob Dylan in concert next year

In [2] the present evidence is clear – the black clouds. In [3], the present evidence may be the tickets for the concert that the speaker has seen on Luke’s desk, or it may simply be the knowledge in the speaker's mind that s/he has somehow acquired.

Modal (will) - Lindsay will fly to New York next week.

Will is a modal and, like the other modals, has two core meanings. The two core meanings for most modal are:

(a) the 'extrinsic' meaning, referring to the probability of the event/state (b) the 'intrinsic' meaning, reflecting such concepts as: ability, necessity, obligation, necessity, permission, possibility, volition, etc.

The extrinsic meaning of will is exemplified in:

4. Emma left three hours ago, so she will be in Manchester by now.
5. There will be hotels on the moon within the next 50 years.
6. The afternoon will be bright and sunny, though there may be rain in the north.

In all three examples, the speaker suggests 100% probability, i.e. absolute certainty. (MAY would imply possibility, MUST logical certainty, to take examples of two other modals). Note that while certainty in [5] and [6] is about the future, in [4] it is about the present. It is the absolute certainty, in the minds of speaker/writer and listener/reader, that can give the impression that forms using ‘the will future’ are some way of presenting ‘the future as fact’. Some writers therefore call this form ‘the Future Simple’. Weather forecasters, writers of business/scientific reports, deliverers of presentations, etc, frequently use will, and learners who encounter English more through reading native writers than hearing native speakers informally may assume that it is a 'neutral' or 'formal' future. In fact the particular native writer or speaker is simply opting to stress certainty rather than arrangement, plan or present evidence.

The intrinsic meaning of will is exemplified in:

7. I'll carry your bag for you.
8. Will you drive me to the airport, please?
9. Jed will leave his mobile switched on in meetings. It's so annoying when it rings.

These examples show what we might loosely call volition, the willingness or determination of the subject of the modal to carry out the action. Note that [9] is not about the future, and in [7] and [8] the futurity is incidental. It is context rather than words which gives the meaning.