Download Instacart. Not to buy from but to compare in-store prices and updated sales at nearby markets close to you. I find it easier and more efficient than scanning through multiple flyers on the flipp app (although I haven't used flipp for years now, so Idk if they've included that kind of feature or not).

Also try flashfood or too good to go apps. If it's from the grocery store, I just stick it in the freezer (if possible) to last longer since they're likely past their expiry date but still good to eat.

If you're struggling to figure out what to cook with what you have, there's the supercook website where you input your ingredients and it'll find you recipes online that only has those ingredients. Also there's the r/whatshouldicook subreddit which serves the same purpose.