Travel is a verb, so it's something people do-going to different places. "I travel to different countries every other month." Trip usually means something short and close by. "I took a trip to the grocery store." or "I took a trip to my aunt's house." Journey usually means something long and far away. "I took a journey to find myself." or "I took a journey through China."

Travel is a general term to go from one place to another place. Example= I really like to travel in weekends. A trip usually refers to traveling to a place and returning back to where you started. Example- I went on business trip to china and spain. A journey usually implies traveling from one place to another (not necessarily returning to where you started). It sometimes refers to the length of time taken to go from one place to another. Example- It is a two days journey by train. Hope you understand well now!!

"Trip" is also an American slang that refers to the experience of using any hallucinogenic drugs. For instance, [As a verb] "Hey, homie, what are you trippin' on?" [As a noun] "Wow! That trip was crazy last night."