Soil -- Organic Potting Soil vs./and Compost

Hi all -- In short, I'm currently in Fiji, so getting top-tier soil components is a challenge. I've searched island-wide and been unable to find typical components that are easily found in the Americas and Europe. Shipping charges to Fiji are astronomical, so buying abroad is not an option. All I have been able to find is "Organic Potting Soil" and "Compost" imported from the NZ company Tui (Photos attached). There is no NPK ratio listed anywhere on the package or on their website -- Not helpful haha! Given the uncertainty, I'm looking for general soil thoughts/recommendations for a new grow. There is no perfect option, but any thoughts would be helpful.

Should I start the grow w/ 100% 'organic potting soil' and include parts compost later in the grow or include a bit at the beginning? Do I need compost at all? I do have a small shipment of FoxFarm coming my way (Big Bloom, Grow Big, and Tiger Bloom), so hopefully that will help me augment for soil limitations. I have soil and water pH instruments, so I'm also able to check pH. I'm a new grower, so any thoughts would be helpful! Thanks all.

Yeah compost is great to add. Mix native soil with compost and give it a try. Log your ratios on paper, log when you started to see deficiencies and what types. I have all the blessings of a Home Depot but i still would rather master my local soil with local inputs. I pretend im like you, stuck with what i got. You got any pine trees? Go scrape the top layer of fresh pine needles away and dig up that first 4inches...that my friend is Grade A mother earth compost, you aint gotta buy a thing.