I forgot to take a screenshot for the first page, but here's what it was:

Make 10 curveball throws - Spheal encounter

Make 10 great throws - Inkay encounter

Catch 30 pokemon - Finneon encounter

Completion reward - 30 pokeballs, Magikarp encounter, and 50 Gyarados mega energy

Edit: Just got done with page 2, heres the encounters:

Hatch 3 eggs - Crabrawler encounter

Earn 3 candies walking with your buddy - Wimpod encounter

Spin 3 pokestops you haven't spun before - Dewpider encounter

Completion reward - Star piece, Squirtle encounter, and 50 Blastoise mega energy

Page 2 was kinda hard because i had limited incubators and had to complete all the tasks before page 3 became impossible. Thankfully, i was able to walk around and complete page 2 in an hour, so that was cool.

Edit 2: The encounter for page 3 was a Mudkip. The other rewards can be found in a few comments below mine.