“Five minutes” isn’t going to cut it - you need to give her a metric that she understands. She doesn’t understand time.
So you can do it in terms of turns, like one/two/three more turns on the slide. Or you can use a visual colour system on a keyring - green, amber, red. So when it’s green we’re playing, when we switch to amber that means it’s going to end soon, and when we turn it to red that’s the end.
Or if your little one knows more numbers than colours you can do the same but 3, 2, 1 instead.
Again, choices, it doesn’t need to be a battle. Don’t allow it to be one. It’s okay if she wants both choices, but that doesn’t mean she can have both, and if she can’t pick then a simple “Okay, you’re having a hard time choosing so mummy will help and pick the pink top today.”
If she cries or tantrums, that’s okay. A simple “I know it’s frustrating when we struggle to make a choice, isn’t it? It makes me feel frustrated too.” And move on.
If you try and stop her crying, cajole her, try to fix it, reason with her etc that’s just going to exacerbate it as you’re lingering on it.
It doesn’t matter if she screams
all the way round the supermarket because she wanted to be carried instead of walking (been there, never happened since). It doesn’t matter what everyone else thinks - you’re not parenting nosey Bob and Barbara in the corner who aren’t going to be there days, months, years down the line. You’re parenting your child.
I know you’re trying, and it is hard when their language isn’t up to scratch, but it is important to do the research into child development and emotional development, because when we don’t, that’s when we make the problem unintentionally worse.
I recommend Laura Amies/Nanny Amies and Big Little Feelings as great free resources on this topic.