"A nos actes manqués" What's the meaning of this expression?

d'ailleurs & en plus Can we use "d'ailleurs" the same way we use "en plus"?

bien comme il faut. Could I have some examples sentences using this expression of how to use it. (With English translation if possible)

"ça m'etonne" = I'm surprised? translated, 'ça m'etonne' means 'I'm surprised', but when used in conversation can it mean "that doesn't surprise me" "It's going to rain today" "yeah, the clouds are grey so 'that doesn't surprise me'. "Il va pleuvoir aujourd'hui" "oui, les nuages ​​sont gris donc 'ça m'étonne'.

How do you say 'about' in french? For example - "the book/film is about...." or "they are taking about......""il s'agit de...." can we use this also?

"pourtant" - many meanings? I hear this word used a lot but still not sure myself how and when to use it. Could you give me some example sentences with it used in different ways (with English translation please)

parle-t-on... parle = verb, on = pronoun but what is the 't' in the middle and why is it there?

esperons = hopefully? when we use 'esperons' on its own, does it mean 'hopefully'? As in "hopefully, I will pass my test tomorrow.." "esperons, je passe...." or is it better to say "j'espere que je passe...."?

il faut - must? Why do we say IL (he) faut aller... when I want to say - "I/you/we must go" Can we say "je/tu/nous faut aller"?