Here are some strategies you can use when reading a text to better understand it:
Skimming:
Read the titles and subtitles to find out what the text is about
Look at the pictures to give you more information about the topic
Read the first and last sentence of each paragraph
Do not read every word or sentence, look for important keywords
Scanning:
Do not read every word, instead try to scan the text until you find what you are looking for
Use the titles and headings to help you
try to think of questions you have about the text, this will help you get the information you are looking for and will help you understand the text better