Learn Hardcore Japanese: watasi ha mainiti gakkou made arukimasu.

は marks the topic of the sentence. It’s like saying “As for me…” in English. Although it often coincides with the subject, its main job is to set what you’re talking about rather than spotlight new information.

Why not use が instead of は here?

が introduces or emphasizes a subject that’s new or important. は, on the other hand, assumes the topic is already known or given. Since “I” is the assumed topic in “I walk to school…,” we naturally use は.

What does 毎日 mean and why does it come before everything else?

毎日 means “every day.” It’s an adverb of frequency, so it modifies the verb. In Japanese you can put such adverbs near the beginning of the sentence (just before the verb or even at the very start) to highlight the routine aspect.

What is the function of まで in 学校まで?

The particle まで marks the endpoint or limit of movement: “up to” or “as far as.” So 学校まで literally means “(walk) as far as the school,” i.e. “to school.”

Can I use 学校に or 学校へ instead of 学校まで?

Yes. 学校に and 学校へ both mark a destination and mean “to school.”
• に is a neutral destination marker.
• へ emphasizes the direction toward.
まで specifically highlights the endpoint (“up to that point”), which is slightly different in nuance.

Why isn’t there a particle like を after 学校?

The verb 歩く (“to walk”) is intransitive—you don’t “walk” something, you walk to/at a place. を marks a direct object (the thing being acted on), so it doesn’t apply here.

Could I say 歩く instead of 歩きます?

Yes. 歩きます is the polite non-past form. The plain/dictionary form is 歩く. In casual speech or writing you might say:
私は毎日学校まで歩く。

Does 歩きます mean “am walking,” “walk,” or “will walk”?

Japanese non-past verbs cover both present and future. With 毎日, this sentence describes a habitual action (“walks”). Without a time expression, context would decide if it’s a present habit or a future plan.

Why is は pronounced wa when it’s written with the hiragana for ha?

Particles have special pronunciations. The hiragana は is read ha in words, but as the topic particle it’s always pronounced wa. (Similarly, を is written wo but pronounced o.)

Why does the verb come at the end?

Japanese uses a Subject-Object-Verb (SOV) order. Adverbs, objects, locations, etc., all precede the verb. So 私は／毎日／学校まで／歩きます follows the normal SOV pattern.