か

ますか just asks for the plain fact (行いきますか). んですか asks about something you can already see is going on (行いくんですか).

ですか asks flat out, the everyday choice (これですか). でしょうか softens it, leaving room for doubt, and reaches upward (よろしいでしょうか).

か just asks for a fact, at any politeness level. の asks more softly about what you notice (泣ないてるの？).

か sits inside each choice, and the two just sit side by side (コーヒーにしますか、紅茶こうちゃにしますか). それとも sits between them, so the second choice can start a new sentence.

か at the very end turns the whole sentence into a question (行いきますか). か partway through needs a verb somewhere later in the sentence (いつ終おわるか知しりません).

ませんか often sounds like an invitation, not a real no/yes question (一緒いっしょに行いきませんか). か plus ません only reads as a literal question when nothing suggests an invite (お酒さけは飲のみませんか).

Both are the particle か, and the two can appear together (どこか行いきましたか). The end か asks the question, this か just hides the place (どこか行いった？).

か asks for something you never knew (お名前なまえは何なんですか). っけ says you once knew it, so it sounds odd on first meeting (お名前なまえは何なんでしたっけ).

か asks for something you don't have (三時さんじですか wants the time). ね offers something you already believe, and wants a nod (三時さんじですね).