Is it advisable to marry a young man who shakes hands with women, knowing that I aspire to study Islamic knowledge and fear that my marriage to him will affect my religious ambitions, and that I do not see myself currently qualified for marriage?

A husband should be chosen based on his religion and character, in accordance with the Prophet's (peace be upon him) saying: "If there comes to you one whose character and religion you are pleased with, then marry him [to your daughter]." This should be done while considering the totality of his attributes and morals, and the key is that he is generally acceptable. If the current suitor is such, then it is preferable to accept him. However, if you reject him in anticipation of someone more religious, there is no sin in that. It is advisable to consult with the wise among your family or righteous women, then perform Istikhara (prayer for guidance). The preponderant view after Istikhara is to proceed with the matter unless Allah turns you away from it, with the reminder that frequent rejection of suitors and exaggeration in conditions can lead to undesirable consequences.