Yes, it's a challenge. Especially in the beginning.

If you are using LingQ. Look at some of the beginner sets of lessons and ultimately the mini stories. The mini stories are basic, but might be a little rough for true beginner unfamiliar with LingQ. However, I think if you take them in smaller chunks at a time it might not be so bad.

As a basic suggestion I would read these multiple times over the course of a day or two. Listening as well. I'd probably move on to a new lesson after a few (spread out) readings and listenings. Perhaps you come back to it later, or simply continue on.

Other suggestions:

1) Do not get hung up on trying to memorize every word. If you don't remember it after a few readings...move on. You'll see these common words elsewhere and eventually things will stick. Some words will not stick after repeated readings. Simply move on. Plenty will stick. Those words aren't going away and you will see them again and again.

2) Don't worry about memorizing every word to a point where you feel you could use it "actively" (speaking or writing). Sure, work on these a little if you like, but remember your passive ( reading and listening) vocabulary will ALWAYS be greater than your active vocabulary. i.e. Don't let your minimal active vocabulary stop you from moving on to the next lessons if you can mostly understand what you're reading.

3) I think primary focus should be on the input side (reading and listening). This is how you will acquire vocabulary very quickly.

Also, for any beginner it could be beneficial to pick up some other book to give you some basic words and phrases and some simple grammer. Teach Yourself or Assimil. Or even a phrasebook (Lonely Planet is pretty good).

Another book you might find helpful for Spanish if you know English well is Madrigal's Keys to Spanish as it highlights many of the similarities between the two (with a few tweaks).

Something else you might want to check out is the youtube channel Dreaming Spanish. They have all levels of videos. Stories are told with pictures.