elizabeth i marriage n heir

out of curiousity but does anyone know/have an idea of what wouldve happened if elizabeth had gotten married but hadnt had an heir?

like would the crown go to her husband or would it have gone to james or someone different depending on which marriage?

It could be either, but i would say her husband. Her sister Mary married Spanish King Philip II and died childless, but towards the end of her life Philip had been very controlling, throwing England into wars for Spanish benefit. The reason the throne passed to Elizabeth was because Parliament managed to get Mary to promise that if she died childless, Philip wouldn't inherit the throne. Mary then named Elizabeth as heir on her death bed. I don't think Elizabeth would be in this same position, as she was much stronger willed to Mary. Her ministers spoke of succession, and she raised her voice at them and banned them from the topic; she was governed by herself, Mary was governed by her ministers. If she had married, then she wouldn't have signed this document and couldn't be made to.
That being said, Elizabeth's potential suitors were mostly Catholic, but James was Protestant so Elizabeth would probably prefer James to inherit the throne over her husband to keep religious continuity. To answer your question, I would say it depends on whom she married. A Catholic, James. A protestant, her husband.

Wrong. The right to the throne only passes down a blood line, so no change. It would have been James.