Shopify website refinements

Hello,
I have recently set up my first ever website and haven't 'launched it' as such yet.
I require some adjustments that I cannot figure out myself.
website www.paperspaceboutique.com

I will list adjustments needed.

1. update cart, complete your purchase and continue shopping buttons on cart page all the same colour as the navigation menu background with white text and all aligned.

2. all page titles and collection page titles centred.

3. all titles udner collection photos made bold
4. logo in header centred, I would then like a coloure
d thin header above this with search all products box in top left, shopping basket top right, with the sign in/create account to the left of this. See www.jenslittlet.com for what I mean there.

5. All collections to link back to the collection list page they came from. i.e when on a product it would say Home > handcut papercuts > animal papercuts > wolf canis (as an example) whereas right now when on a collection such as animal papercuts it just shows home > animal papercuts it doesn't remember the collection page list 'handcut papercuts' I want this to work for all my product ranges such as digital prints, gifts etc so it remembers the page it came from.

6. Finally I would like the copyright logo and payment icons centred in the bottom/footer rather than to the left and right of the footer.

If you could provide a cost and timescale for this please.
thank you, Lindsey