Here are the steps of English grammar in very simple and short sentences.
First, learn the parts of speech. These are the building blocks. Nouns name people, places, or things. Pronouns replace nouns. Verbs show action or being. Adjectives describe nouns. Adverbs describe verbs. Prepositions show relationships. Conjunctions connect words. Interjections show emotion.
Next, build a sentence. Every sentence needs a subject and a verb. The subject does the action. The verb is the action. The object receives the action. Keep your sentences simple at first.
Then, learn the tenses. Tenses tell when things happen. Past tense is for yesterday. Present tense is for today. Future tense is for tomorrow.
After that, practice punctuation. Use a period to end a statement. Use a question mark for questions. Use commas to separate ideas.
Finally, read and practice daily. Grammar improves with use.