Not sure what you mean?
So - I was reading ( Imparfait/Imperfect) je lisais
I was going to read j'allais lire ( imparfait/ imperfect) of aller to go, followed by infinitive of manger to eat.
It's not the tense that makes it followed by the infinitive but the meaning - to read.
You can have an infinitive after any tense.