Quality guest posts in home topics, I want to rank on the first page for these below keywords with guest posts -- 3

I want to rank on the first page for these below keywords:
Already have a good ranking for some of them, how long does it take? URL: https://greenhousedecor.com.au/collections/shelves
shelving units
display shelf
timber shelves
wooden bookshelf
display shelving
timber bookshelf
wooden shelving
wooden bookcase
oak bookshelf
open bookshelf