Learn Dutch: Ik heb een hond en jij hebt een kat. - I have a dog and you have a cat.

The verb hebben (to have) changes depending on who is doing the action. For ik (I), you use the basic form: heb. For jij (you), you usually add a -t, making it hebt.

Could I use je instead of jij in this sentence?

Yes, but jij puts more emphasis on the word "you". Because this sentence is comparing what I have with what you have, using jij sounds more natural to emphasize the contrast between the two people.

How is the word een pronounced here?

Even though it has a double 'e', een (meaning "a" or "an") is pronounced like "uhn" (similar to the 'a' in the English word "about"). If you pronounce it with a long "ay" sound, it means the number one, which is written as één.

Does the word en (and) change the word order in the second half of the sentence?

No. The word en simply links two normal, independent sentences together. The second part (jij hebt een kat) keeps the standard Dutch word order: subject (jij), verb (hebt), and then the rest of the sentence (een kat).