hey i need some help is it legal to keep orb weaving spiders

They are not illegal to keep.
The only problem is that for them to be able to make a decent size web you will need quite a large enclosure and some wind for them to help make their web. I would guess an enclosure of around 1.5 x 1.5 x 2 m tank.
Basically, rather stick to tarantulas or rain/wolf spiders.

I would also really like one of those. My dream is to one day have a Madagascan silk spider (don't know the Sci-Name)

Are you talking about the big orb weavers that sometimes eat birds?
If you are, then you will probably need a tank of 5 x 5 x 5 m atleast. We have pretty much the same spiders here from the family Tetragnathidae, genus Nephila that get just as big, but you cant keep them as pets as their space requirements are too big, plus they only live for around 9 months.

There are curtain spider that should not be kept as "pets".

I can confirm what Cerat says about there space needs.
If you really want to keep orb web spiders Turn your garden into an environment (but only have species that come from your area) for them and they will live and breed and you will be able to have/see then all the time!!!

I have kept 2 small ones before, if you do not give them the right environment they die!!
So get your self a rain spider or some other kind of True spider to keep as a pet!

Try a Black widows they make awesome webs if you keep them in a big enough container,Not sure to what reason of wanting to keep these spider, color, size or Webbing?
There are plenty true spiders that make awesome display spider and do not need half a room to achieve this goal.

And as I said if you give them the right environment in your garden you could have what Hertabest reptile and animal zoo have.
The have hundreds of spider all over the Zoo

Here are some pictures.

Wow cascade, that looks like a place I'd love to visit!