Don't learn words like this:

chair - Stuhl, window - Fenster, kitchen - Küche

but like this:

chair - der Stuhl, window - das Fenster, kitchen - die Küche

Tips for what? What kind of problems specifically?

Anything specific or in general? I don't think there's a logical system behind gendered nouns, you'll just have to memorize them sadly. Der Stuhl (the chair) is male, das Fenster (the window) is neutral, die Banane (the banana) is female. It's completely random.

There are patterns to look out for if what you're having trouble with remembering which gender a noun is: https://sites.lsa.umich.edu/german-resources/grammatik/gender/