There aren't really many solid rules but here are some commonalities between the endings and the gender:
Masculine : - ich, -ig, -ling, -er, -atz, -ag, -ang.
Masculine foreign words: -ant, -ast, -ismus, -or
Feminine : -e, -heit, -keit, -schaft, -ung, -ei,.
Feminine foreign words : -anz, -enz, -ie, -ik, -ion, -tät, -ur
Neuter : -lein, -chen, -nis, -tum, Ge-.
Neuter foreign words : -at, -ett, -fon, -ma, -ment, -um
Indeed there is, try to watch https://www.youtube.com/playlist?list=PLrfupM1_qw4RwHiaLAXla240CxrrMmZcF number 4, 5 and 6.
However, as a beginner I find the rules difficult to remember. I'm inclined to learn the gender by heart instead.
What you heard is perfectly right. Isaldo is naturally also right. it is much easier to learn the gender by heart. The gender is like a syllable of the new word. You have not to learn two words. Your mind makes one of it. It will be used to it that the article gives the words the undoubted feature of a substantive. Learning frequent constructions by heart makes you more confident.
Most nouns ending in -e in German are feminine. However there are quite a few exceptions as only about 86% of nouns ending in -e are feminine. E.g: der Käse, der Name...And also a useful fact : feminine nouns that end in 'e', simply add an 'n' to form the plural. Hope this helped!