Why can't I link Facebook and Instagram to my store and simplify checkout steps?

hello, i need help about something in my shopify store.

  1. i don’t know why i can’t connect facebook & instagram to shopify..
    i was inactive for a while and than i got that message.

i’ve contacted with facebook support and they told me is there no restrictions from their side.
so they said i should contact shopify about this issue..

  1. when i go to checkout in my shopify store, i have 4 steps to the checkout..
    i need to press “continue to shipping” → “continue to paymet” → “pay now” and then i need to insert credit card details.

as you can see above, it’s my website.

and this is other shopify store, (i censored the other shopify store name)
i want it to look like that..

Thanks for help!

and very sorry if i wasn’t clear enough..

english is not my first language as you can see.

I didn’t fixed it yet