A jew told me the judaism doesnt convert to the people but according to jewish people we have to obey the rule

rules of the 7 commands of Noaj.. one of those rules. it's not to woshirp another god except God.. so my question is how can you say that? if many people dont know God..and most of them never heard of judaism or noaj laws but a rabbi wrote they have to find for God..well if you are not looking for convertions.. why do we have to obey those laws for gaining a place in the heaven or paradise? I think God will accept people from different religions by the actions..becuase many people believe in one God but they dont do good actions..I agree some laws of Noaj are universal but it reminds too much the judaism wants us to believe in the God from the Bible..