-ing form after a verb

You can say, I want to travel, or I hope to travel, but you cannot say, "I enjoy to travel".
             Instead you must say, I enjoy traveling.

Here's a list (NB non-exhaustive) of verbs that are followed by an -ing form in the next verb; you should learn the list by heart:

admit, appreciate, avoid
can't help, can't stand, consider, contemplate
delay, deny, detest, dislike, don't mind
endure, enjoy, escape, excuse
face, fell like, finish, forgive
give up
imagine, involve
leave off
put off
resent, resist, risk
suggest
understand

You may remember the verbs better if you notice that most of them involve an (act of) emotion.