Bonjour Lalala di da,
Yes there are rules regarding the last letter pronunciation. It can seem quite tricky as these rules differ from a letter to another. Some rules are consistent and some have many exceptions
. That is unfortunately the difficulty, but it is the way French has evolved with time.
To get the basic of this letter ending pronunciation notion, here is a general rule.
When Not to Pronounce Final Letters
As a rule of thumb, do not pronounce final letters. However, keep in mind that we pronounce the letters b as in club ("club"), c as in toc ("tap"), f as in bref ("brief," "in short"), k as in anorak ("waterproof vest"), l as in fil ("thread"), q as in cinq ("five"), and r as in car ("because") when they fall at the end of a word.
The other French consonants are usually silent at the end of a word, with some exceptions, as with many proper names or words borrowed from other languages or when linking words are mandatory, as in les oranges ("the oranges"), pronounced [lezoranj], or ils ont ("they have") [ilzon].
On the other hand, final letters pronounciation are usually taught by categorizing according to each tricky letter pronunciation rather than the final letters for better understanding and not go through the entire alphabet
. So let's just start with the letter -e.
The silent letter -e:
The silent -e is almost** always spelled with the letter -e without any accent, and we can pronounce it as in verrai ("I'll see") or drop it as in the last -e in quellE ("which," "what").
The requirement to pronounce or not pronounce the silent -e depends on the emphasis the speaker wishes to express. For example, someone can say Je TE le dis ("I tell you.") or JE te le dit ("I tell you"), and the language register.
The silent -e is more commonly pronounced in formal French than informal French, in which speech is faster and less articulate. For example, you may hear in informal speech, Je t'l'dis ("I tell you.") where the speaker does not pronounce at all the letter -e sound, because he or she is speaking very rapidly.
The Different Pronunciations of the Written Unaccented -e:
The unaccented -e is not always a silent -e; some unaccented -e's are pronounced with the -é sound or the -è sound when placed in front of double consonant*, as in tennis ("tennis"), or in front of two articulately pronounced consonants, as in restaurant ("restaurant"). These pronunciations may vary from region to region, but that won't affect comprehension.
*When the double consonant is a double -s preceding the letter -e, we pronounce this letter as the letter -e from the alphabet. It is also the case when the letter -e is part of the prefix re-, as in repartir ("to leave again").
Deciding Whether to Pronounce the Silent e
In most words or phrases ending in -e, the final -e is silent and is always dropped. For example, we drop it when the silent -e precedes a vowel, as in une autre ami, pronounced [hun otr ami], or precedes a consonant, as in elle joue ("she plays").
Some exceptions are the pronunciation of the silent -e, whether required or optional, in:
A.) One-syllable words:
1. ce ("this")
2. de ("of")
3. je ("I")
4. le ("it")
5. me ("myself")
6. ne (part of the negation form)
7. que ("that")
8. se [reflexive element of the verb, as in se maquiller ("to put make up on")]
9. te ("you")
It is required when a word starting with a silent h- follows it, as in the aspired h- in ce homard ("this lobster").
It is optional when a word starting with a consonant follows it, as in informal fast speech, as with Je n'suis pas là ("I'm not here."), which you can encounter in comics, for example. In formal French, it should be Je ne suis pas là ("I'm not here.").
B.) A phrase or word when the silent e is placed in the first syllable, as in Levez-vous à six heures ("Wake up at six o'clock a.m.").
C.) A phrase or word when the silent e is not in the first or last syllable and is preceded by one or more consonant sound, as in Je regardez ce film ("I watch this movie") or l'appartement ("the apartment").
I hope I anwered your question !!!!