How to express what I like and dislike?

To express such an opinion, you can use the verb "aimer" which means "to like". It's a regular verb from the 1st group (ending in -er) which is quite easy to conjugate, and once you understand the conjugation, you'll be able to use other verbs from the 1st group. Basically to say that you like something it is subject + verb (like) + object. I you want to express the fact that you like an action or to do something it is subject + verb (like) + infinitive verb. There is no word such as "to" before the infinitive verb. So expressing that you like to eat would be "j'aime manger". If you want to say that you like to eat something it would be subject + verb (like) + infinitive + object for example "j'aime manger des tomates" (I Like to eat tomatoes). On the contrary, to express what you don't like, you can add the word "pas" after the verb "aimer" and before the infinitive. Expressing that you don't like to eat would be "je n'aime pas manger".