Giving  opinions in Spanish. Telling someone what you think.

The typical way to precede your opinion could be:

Creo que =  I believe that...
En mi opinión = In my opinion ...
Pienso que = I think that ....

Note that if you search for "creo que" or "pienso que" on internet you will see people debating when to use the subjunctive afterwards.
For an A1 student the subjunctive if a bit too difficult to be worried about. . In the sentences in this lesson we don't have to use the subjunctive because they are declarations of opinions rather than speculation about something. 

However if you use the negative "creo que no"  = "I don't believe that" You would probably have to use the subjunctive. 
For example: "no creo que haya ningún problema" - I don't think there would be any problem. 

There is also an example of this in the examples. "no creo que el jefe sea un idiota" = I don't believe that the boss is an idiot. (the "sea") is the subjunctive bit..

There is also another use of the subjunctive in the examples. Look for "viniera"
At this stage just note that the subjunctive exists but don't worry about it too much. 

The opinions expressed in this lesson are just examples. No animals were harmed in the making of this lesson.