Bármennyire is meredek a lejtő, túrabottal óvatosan megyünk.

It means however or no matter how. It introduces a concessive idea: something is true even if the condition is extreme.

So:

Bármennyire is meredek a lejtő
= No matter how steep the slope is

Not really, at least not in the usual direct way.

The word is often means also / too / as well, but in patterns like bármennyire is, it helps create an emphatic concessive meaning: no matter how, even if, however much.

So in this sentence, you usually would not translate is separately. It is part of the structure bármennyire is ...

Because in Hungarian, the verb to be is often omitted in the present tense, third person singular.

So:

A lejtő meredek.
literally: The slope steep.
actual meaning: The slope is steep.

That is completely normal Hungarian. The is you see in the sentence is not the copula is; it is the particle discussed above.

Because bármennyire directly goes with meredek, so the adjective naturally comes first:

bármennyire is meredek a lejtő
= however steep the slope is

The version a lejtő meredek is also grammatical as a simple statement, but in this clause the focus is on the degree of steepness, so meredek comes earlier.

Lejtő means slope, incline, or hillside depending on context.

Here it is the thing that is steep:

meredek a lejtő
= the slope is steep

Túrabot means hiking pole, trekking pole, or walking stick.

The ending -val / -vel means with, but this suffix assimilates to the final consonant of the word.

So:

túrabot + -val → túrabottal

That is why you see the doubled t.

So túrabottal means with a hiking pole / with trekking poles.

Hungarian often uses the singular when talking about a tool or means in a general way.

So túrabottal does not necessarily emphasize exactly one pole. It can simply mean using that kind of equipment.

English may sound more natural with with hiking poles, even though Hungarian uses the singular form.

Because Hungarian often leaves out the article in general instrumental phrases.

Here, túrabottal means something like using a hiking pole / with hiking poles in a general sense, not with the specific hiking pole.

If you said a túrabottal, that would point more strongly to a particular pole: with the hiking pole.

Óvatosan means carefully or cautiously.

It comes from the adjective óvatos = careful / cautious, plus the adverb-forming ending -an:

óvatos → óvatosan

So:

óvatosan megyünk
= we walk/go carefully

Because Hungarian usually does not need the subject pronoun if the verb ending already shows who the subject is.

megyünk = we go / we walk

The ending -ünk already tells you it is we, so mi is normally omitted unless you want extra emphasis.

Literally, megyünk is we go. But in context, it often means we walk or we proceed.

In a hiking sentence like this, English usually prefers walk:

túrabottal óvatosan megyünk
= we walk carefully with hiking poles

So the exact English choice depends on context, even though the Hungarian verb is simply menni = to go.

Because the first part is a subordinate clause:

Bármennyire is meredek a lejtő,
= No matter how steep the slope is,

and the second part is the main clause:

túrabottal óvatosan megyünk.
= we walk carefully with hiking poles.

Hungarian, like English, separates this kind of introductory subordinate clause with a comma.