missing "from"  -- (MW) The untranslated word "from" means "from" in both locations and when referring to a source or a cause. It also means the instrument "by" which a thing is done and "away from."

I -- This is from the first-person, singular form of the verb.

am -- This helping verb indicates the present tense of the verb. It is used here to form the present, progressive tense, which doesn't exist in Greek but which can smooth the flow of English sentences..

telling -- The word translated as "telling" is the most common word that means "to say," "to tell," and "to speak,"  but when used with an objective noun or pronoun, the sense is "say of" or "speak of."  When two accusative objects are used, the sense is  "say of him this," or "call him this." The form Jesus uses to describe his own speaking can be either indicative, "I say/tell" or subjunctive, "I should/could say/tell."  It also has many ancillary meanings such as "to count" ("to number" or like we might say, "to recount" a story) or "to choose for yourself."

you -- The Greek pronoun "you" here is plural and in the form of an indirect object, "to you," "for you," etc. As the object of a preposition, this form implies no movement, but in a fixed position or events occur at a specified time or while the action was being performed.

now -- (CW) The Greek word translated as "now" means "just" or "exactly and "now" in the sense of "just now" when applied to time. It is not the common adverb usually translated as "now" but one that means "just now" or "as yet" implying a change in the future.

before -- The Greek word translated as "before" means (of place) "before," "in front of," (of time) "before," (of preference), "rather than," "more than," and so on.

it -- (WW) The word translated as "it" is the Greek definite article, without a noun, it has the sense of "the one." The Greek article is much closer to our demonstrative pronouns ("this," "that," "these," "those") than the English "the." See this article for more. This article makes the infinitive acts like a noun.

happens, -- (WF) The word translated as "happens" means "to become," that is, to enter into a new state. In Greek, especially as used by Jesus, it is the opposite of "being," which is existence in the current state. When applied to events, this word means "to happen," "to occur," or "take place." This is not an active verb but an infinitive used as a noun describing the action, "the happening" or "the occurrences.".

so that , -- The word translated as "so that" introduces a statement of fact or cause, "for what," "because," "since," and "wherefore."

when -- The Greek word translated as "when" introduces a phrase that explains a certain condition so "whenever" or "since."

it -- This is from the third-person, singular form of the verb.

does -- This English helping verb is used to create questions, commands, negative statements, and smooth word flow in translation from Greek

happen, --  The word translated as "happen" means "to become," that is, to enter into a new state. In Greek, especially as used by Jesus, it is the opposite of "being," which is existence in the current state. When applied to events, this word means "to happen," "to occur," or "take place."

you -- This is from the second-person, plural form of the verb.

will -- (WW) This helping verb "may" indicates that the verb indicates a possibility, the subjunctive. Helping or auxiliary verbs are needed to translate the Greek verb forms into English.

believe-- The Greek word translated as "believe" does not apply to religious belief as much but trusting or relying upon other people, especially their words. Jesus usually uses it in contexts, such as the one here, that apply to trusting words.

that -- The word translated as "that" introduces a statement of fact or cause, "for what," "because," "since," and "wherefore."
I -- The pronoun "I" is used here. Since, as the subject of the sentence, it is part of the verb, its explicit use accentuates who is speaking "I." Saying "I myself" captures this feeling in English.

missing "myself" -- (MW)  The subjective pronoun repeats the information in the verb so it should be repeated in English like "I myself."

am -- The verb "am" here is the common form of "to be" in Greek. It means to have a certain characteristic or remain in a certain condition. It also equates terms or assigns characteristics.

similar meaning, but it confuses the actual vocabulary.

who I am. -- (IP) There is nothing that can be translated as "who I am. " in the Greek source.