opencart jurnal theme version 3 customization

hello
i want customize jurnal opencart theme where already installed opencart multivendor script.

i explained all details.............check customize point.

hello i want customize opencart jurnal theme version 3.already installed opencart multivendor marketplace.
now will show all point with details.as a multivendor website few point will be add by seller.so keep in mind.

now i explained all point full details

desktop version................

out theme link https://www.journal-theme.com/v3_9/index.php?route=common/home


on top header line right side add text with link.......Become A Seller | Seller Login | Returns |

and same line middle position add this text with link.....Buyer Protection | Helpline 18001114210 ( 9.30 am - 9.30 pm )

then beside search box right side add text with highlight background color ......Sell product.
then next menu all category want beside.

FOOTER ....................

footer background make white color and text size make small.
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CATEGORY PAGE --- want show per line 4 products and filter make left side and filter text make small.then make currency ruppes icon and when keep mouse
any products images showing black blackground with add to cart....remove it or make it white for whole website.

PRODUCTS DETAILS PAGE - main image size and products title size make small.then add some text field which seller will filled product 
upload time......Shipping and free shipping and warranty,delivery time.....this text filed seller will add product upload time.

this text will be fixed for all time.....
Buyer Protection - this text will fixed with red background color same to same like gozefo.com(buyback gurantee)
7 Days Return --this line will be as semi headline and under this will be add text...if products not described or damaged or not received........this text if click will be open returns page.

then add next line we accept cash on delivery,online payment.then nextline add text YAMDEAL ASSURED-THIS TEXT WILL BE semi headline text and under this text will be add.........This Products Quality checked Throughly Tested By Expert.this text will be fixed for all time.

then add Contdition text........products upload time if seller will select among 3 any 1 options.if select new or certified refurbished or certified 
used.......will show this text with question.if u want idea visit togofogo.com 

buy now button make same to same size,color like gozefo.com
then products description given full screen.give left and right space like gozefo.com
after click buy now now button to complete order want same few filed and easy step like gozefo.com

for mobile or other device chance point........

products details page......1st will show main image then product title then price,then in stock,then model,then weight and brand icon,then other text which u added then should show products details information.
down side you can see add to cart button make it buy now button same to same gozefo.com

then remove black border from this options.....related product and most viewed+people also bought+you might like+from same brand