Welcome to the group Oscar Charlie,
RT's points reflect my thoughts. You are not expected to know all the types, ATC probably does not either!
Sooner or later you will be alone in an aircraft without anyone to ask.
Yes, and when you are, either someone on the radio will be able to help you, and if no one is available to help on the radio, you probably have a lot more space and freedom around you, so a hurried decision will not be required.
Historically, type identification is something of a self challenge for pilots. It is worth the effort in the long term, though not the worry in the short term. There are books specifically produced with that in mind, you will see silhouette three view images for each type, and be able to distinguish features. These date back to World War 2, when attacking one of the good guys became a new risk to manage.