There are a number of differences between these organisms and these are as follows:
1) Reproduction
Amoeba: Asexual
Paramecium: Sexual by conjugation
Euglena: Asexual
2) Nutrition
Amoeba: Heterotroph by phagocytosis
Paramecium: Heterotroph by predation
Euglena: Autotroph by photosynthesis and heterotroph by ingestion
3) Locomotion
Amoeba: Pseudopodia
Paramecium: Cilia
Euglena: Flagella
Hope this answers the question. Have a nice day.
