Meaning: "To make, cause to become"
* enchant: to fill with magic, to charm
* encourage: to inspire with confidence
* enrich: to make richer, to improve
* enlarge: to make larger
* enable: to make possible
* endanger: to put at risk
* enfeeble: to make weak
* enfold: to wrap around
* engulf: to swallow up
* enhance: to improve
* enliven: to make lively or cheerful
* enrage: to make angry
* enslave: to make a slave of
* entail: to involve as a necessary consequence
Meaning: "Into, in, on"
* enclose: to put within a boundary
* encase: to cover or enclose
* embed: to fix firmly into something
* encode: to convert information into a code
* encompass: to include
* encounter: to meet
* entrap: to catch in a trap
Meaning: "To put in, to cover, to dress"
* encase: to enclose in a case
* enrobe: to dress in a robe
* ensheath: to cover with a sheath
Meaning: "Completely, fully"
* entire: whole, complete
* enthral: to hold spellbound
Other
* enemy: someone who is hostile
* enigma: something mysterious or puzzling
* enjoin: to command, to order
This is not an exhaustive list, but it gives you a good idea of the variety of ways the prefix "en-" can be used. Remember that the meaning of the prefix can also be influenced by the word it is attached to.