何
何 means “what” in 何をしていますか。It asks which action the other person is doing; it appears before を when asking about the object or activity.
を
を marks 何 as the object of the action in 何をしていますか。It also marks the thing being acted on, as in 水を飲んでいます。
して
して contributes “doing” in 何をしていますか。It is the て-form of する and connects with います to describe an action in progress; the same form appears in しています。
います
います helps express that the action is continuing in 何をしていますか。 and しています。Here it follows the て-form and gives the polite “be doing” meaning.
か
か marks the sentence as a question at the end of 何をしていますか。It is used after the polite sentence form to ask what someone is doing.
今
今 means “now” in 今、食べています。It specifies that the eating is happening at the present time and can appear before an action that is happening now.
食べて
食べて contributes “eating” in 今、食べています。It is the て-form of 食べる and connects with います to describe eating in progress; 食べています is a reusable polite expression for this action.
水
水 means “water” in 水を飲んでいます。It is the thing being drunk and is followed by を when used as the object of 飲んでいます。
飲んで
飲んで contributes “drinking” in 水を飲んでいます。It is the て-form of 飲む and connects with います to describe drinking in progress; 水を飲んでいます can be used when telling someone what you are doing now.
夕食
夕食 means “dinner” in 夕食を作っています。It is the meal being made and is followed by を before the action that is being performed on it.
作って
作って contributes “making” in 夕食を作っています。It is the て-form of 作る and connects with います to describe making dinner in progress; 夕食を作っています is useful when explaining a current activity at home.
自分
自分 identifies the person’s own self in 自分の部屋を掃除しています。, so 自分の部屋 means “one’s own room” in this dialogue. The pattern 自分の followed by a noun can identify something as belonging to oneself.
の
の links 自分 and 部屋 in 自分の部屋, showing the relationship between “one’s own” and “room.” It appears between the describing word and the noun it specifies.
部屋
部屋 means “room” in 自分の部屋を掃除しています。It is the room being cleaned and, as a larger noun phrase, is followed by を.
掃除
掃除 names the cleaning activity in 自分の部屋を掃除しています。Together with しています, it says that the speaker is cleaning the room now. This expression is useful when reporting cleaning as a current activity.
シャワー
シャワー means “shower” in シャワーを浴びています。It is the object in the expression for taking a shower and is followed by を.
浴びて
浴びて contributes the action of bathing in or under something in シャワーを浴びています。, which as a whole means “taking a shower.” It is the て-form of 浴びる and connects with います to show that the showering is in progress.