Tips on the long-lasting cleanliness of the car after cleaning

Hello dear car friends! I hope you can help me with a question about car care. Recently I cleaned my entire car thoroughly, but after a few days it looks dirty again. I wonder if there is a way to make the result of my cleaning last longer. I have read online that polishing or growing can help, but there are different opinions and I do not have an electric polisher. However, I have read Can anyone give me a few tips? Had found the following products: SONAX Polish+Wax Color black SONAX PROFILINE EX 04-06 Sonax hard wax politure SONAX P-Ball microfiber cloth But I’ve never done it before and I hate to “suck” my car in which I take the wrong products. Thank you in advance!