Learn French: Je me réveille tôt, mais je me lève tard.

In French, actions you perform on yourself often use a reflexive pronoun. Réveiller means to wake someone else, so to say I wake up, you literally say I wake myself (Je me réveille). The same applies to Je me lève, which literally means I raise myself.

What is the difference between se réveiller and se lever?

Se réveiller means to open your eyes and stop sleeping (to wake up), whereas se lever means to physically get out of bed (to get up). This sentence perfectly highlights that you can do one without doing the other!

Why does lève have an accent mark (è) when the dictionary form se lever does not?

It is a spelling change to help with pronunciation. Because the e at the very end of je me lève is silent, the e right before the v gets a grave accent (è) so it can be pronounced clearly.

Could I change the word order and say Je me tôt réveille?

No, adverbs that describe when or how something happens (like tôt for early, and tard for late) usually go immediately after the conjugated verb. So it must be Je me réveille tôt.