How do I fix marble tabletop to metal base

Here's one way:

https://homeguides.sfgate.com/attach-stone-tabletop-base-89544.html

you will need the right size bolts and screws to get a secure fit - you can buy these at Home Depot type stores -you will need to know the hole size to get correct screws unless you buy a small pack with several sizes in it

You can measure the holes to get the right width and depth.

You can screw plywood to the metal stand 4" shorter than the edges of the marble and glue the marble top to the plywood with silicone caulk.

https://www.youtube.com/watch?v=kRikYTX1IjI

The holes in the marble top are for threaded inserts that are epoxied in the holes. Then the base is lined up with the threaded inserts and screwed on. If the marble top is too large and/or the base not strong enough it won't work. The marble top can crack. Threaded inserts and screws can be found at Home Depot and Menards.

Take photos of the top and base to your local home center and see if they can help you find the right bolts. :)

Yes you will need to know what size bolts to use. I would also put in a dab of glue to make sure they are secure.

You can use a construction adhesive.

Find what you are looking for in a DIY store! Take a picture of fixings and holes and measurements, so you have all the info when you go visit the store.

Try a couple of screws once you line up the whole to base and table top or you could get adhesive like caulk and apply to the base then put the top on no screws

Here's another link that might help:

https://www.garagejournal.com/forum/threads/how-to-attach-stone-table-tops-to-metal-bases.280679/

Yes take pictures and go into a home impovement store they should be able to walk you thru this. If you have an ace hardware go there their employees seem to be much more educated than Home Depot's.