You have done well to ask about matters of your religion and to pay attention to making sure that the source of your provision is halaal and to seek to marry a righteous man. We ask Allaah to make that easy for you.
Working in the production of programs and contests on television in the manner that you describe, which includes mixing between the sexes, songs and music, is work that includes both halaal and haraam, good and evil, because it is proven that mixing, musical instruments and showing images of women are haraam. Whatever is haraam, it is not permissible to produce it or to help in that, because Allaah says (interpretation of the meaning):
“Help you one another in Al‑Birr and At‑Taqwa (virtue, righteousness and piety); but do not help one another in sin and transgression. And fear Allaah. Verily, Allaah is Severe in punishment”
“Verily, those who like that (the crime of) illegal sexual intercourse should be propagated among those who believe, they will have a painful torment in this world and in the Hereafter. And Allaah knows and you know not”
and the Prophet (blessings and peace of Allaah be upon him) said: “Whoever calls people to right guidance will have a reward like that of those who follow him, without that detracting from their reward in the slightest, and whoever calls people to misguidance will have a burden of sin like that of those who follow him, without that detracting from their burden in the slightest.” Narrated by Muslim in his Saheeh (4831).
The part of his salary that results from the haraam part of his work is haraam.
With regard to contests, some of them are permissible and some are haraam. Contests in which the participant pays money, even if it is the cost of a phone call, are haraam and are a type of gambling.
Moreover, it is no secret that working in this environment is not free of other evils, because of mixing and because usually people who work there are included to evil and are lacking in religious commitment.
Hence you should advise this young man. If he repents to Allaah and gives up this work, and finds a permissible job, there is no reason why you should not marry him. But if he continues in this job, there is nothing good for you in him because his wealth is mixed and contains both halaal and haraam, and there is no guarantee that he will not weaken and change because of the environment in which he works.
We ask Allaah to bless you with a righteous husband and righteous offspring.
And Allaah knows best.