My husband is a British citizen, but I'm an Iranian citizen. He wants to immigrate to Spain. I want to know should I go with him or he must go first and find a job? Does it take too long?
Since your husband needs a job to have a right to stay in Spain and sponsor your residence card beyond the first 3/6 months, it would seem easier if he got a job first.
Alternatively, if you have enough savings, you could apply for a residence card as the spouse of an “economically non-active” EU citizen immediately. You could even work yourself on that basis, even if your husband does not have a job yet.