The infinitive form of the word is 'caminar', which means 'to walk'. When you conjugate verbs that end in '-ar' to present tense forms, you have to remember to use an '-a' instead of an '-e'. It's hard to memorize at first, but you can hover over each verb to look up the different conjugations.
You are right. I like this for verbs http://conjugador.reverso.net/conjugacion-espanol-verbo-caminar.html