What is the difference between the velar stop [kʰ] and the ejective [k̛ ]? And how are they pronounced?
[kʰ] is a pulmonic consonant and the ejective
[k'] is a, well, ejective consonant. You might want to check another question here related to ejective consonants and their pronunciation. If you speak English reasonably well (i.e. as either a L1 speaker or a moderately long-time learner) you'll find that the words
<kid> are, respectively,
[kʰɪd]. You can extrapolate on that for other consonants then.