Photos are always helpful. But a couple of points, these aren't palms, they're more closely related to asparagus. Also, they don't have "bulbs", onions have bulbs. The base of the trunk swells up and stores water, but it's still a trunk. When these plants get "pups" (young plants shooting out of the side) those can be carefully removed and planted up separately. But if you can upload some photos it'll make it easier to give specific advice.

Sorry. I guess the photo didn’t upload earlier

Is this a true ponytail palm? Thanks in advance

Perfect! I shall pot them up separately. Any idea how long it will take before they start looking like a long trunk?

I never bothered to separate mine. Yes what you have there is a ponytail. It takes years for them to do anything. Within three years you'll notice the base expanding and the crown will get nice and full. They hold the leaves for a long time unless in severe drought. Which in that case the plants case will shrivel a little when it wants water.

They're definitely not the fastest growing plants for sure. That's an advantage for most people because they can get to be very large/bulky. But it will be variable, depending on your climate.

I live in zone 5 so they will be indoors most of the year. Thanks for all the advice!!