Selam Aleykum,
Welcome to the website sister.
Tell him the reward of ~70 hurlieen is only to those that die as Sheheed. And that he needs to gain more knowledge to correct this and other wrong beliefs of his. If he continues like this, he will get 0 wives in jennah because he will be in jehennam and he will have one very unhappy wife in this life. The minimum size of the people lowest in Jennah is 10 earths and they will get at least two wives, you can correct him by saying this and show him the hadith. If he does die as Sheheed it is better though, as he jokes about. Tell him not to mimick the kuffar and enemies of Islam that mock our religion using this, it is a great honor that we should all work for.
Be patient with him sister, think of how you were before you submitted to Allah SWT and try to show him the proper way of Muslims. Explain to him how you changed and why inshallah. Do not let him make your house un-Islamic. Show him the proofs of Islam, i.e. historic, linguistic, scientific miracles inshallah. That may help. Talk to him about Jennah and Jehenam a lot and stories of the Prophets PBUT and Sahabah RA. Mention hadiths when they come to mind, don't hide your Islam but show out openly- he is your husband, you should be open with him and communicate well inshallah. He sounds like he will reply back with smarmy remarks sometimes so just tell him that it is a great sin to mock our religion, righteous people who Allah loves, etc. show him the ayats etc. for this. Tell him you have changed and would like him too, be open with him inshallah and show him genuine concern for him in this life and the next.
Tell him it is not allowed for him to force you into doing anything Haram and to cut you off from the Halal. If he has a problem with anything you are doing show him the deleel for it, put it in his face, and make him read it. If he still has a problem then you need to first establish the foundations of what it means to be a Muslim. We follow the Quran and Sunnah, 5 pillars, 6 articles of faith, etc. Elhamdulillah he is Muslim though so just work on him slowly, it is hard to change a person 100% so just try to change him little by little. If he wont listen to you take him around other pious people inshallah, when he is in a crowd of them he will act much differently and will likely respect and listen to them much more.... In time inshallah he will learn and correct his actions.
Your situation is difficult, may Allah SWT make it easy for you and guide your Husband. Ameen.
Some men are just immature, inshallah he is just joking around and does not want to hurt your feelings. And remember in Jennah you would not care if he had more than one wife or not, you will only feel good things in Jennah. This life is temporary and just a test so be patient sister.
