Look up English or Esperanto
Look up the English root, then add the ending that matches the job of the word: -o for a noun, -a for an adjective, -e for an adverb, -i for a verb. “I learn Esperanto” is Mi lernas Esperanton. The -n on Esperanton marks the object. You do not change the verb for I, you, or they.
Translate from Esperanto
Read the ending first. Then the root. Londono is London; the -o says it is a noun. Mi estas el Londono is “I am from London.” Questions often start with ĉu (yes/no), kio (what), kie (where), kiel (how), or kiom (how much). That is why “translate London from Esperanto” is a fair first search: the city name is almost the same, plus -o.
How to use the dictionary
Look up a root, then read the example sentences. Pair the lookup with the phrases and lessons when you want a living sentence. Check endings, the accusative -n, and the hats ĉ ĝ ĥ ĵ ŝ ŭ.