Hello and welcome.
There are stickied threads that get so much into detail that your hea dwill spin but rereading them over time will help if you can get the lingo. For now your aim should be to make the discs fly flat and not that high. the usual symptoms for discs flying at 45 degree angle (anhyzer) clockwise rotation for a righthand back hand (RHBH) throw is that the arm drops low after the disc has left the hand. The fingers pul the disc edge down as the disc leaves torquing the disc off of its center of axis. Abbreviated OAT for off axis torque another symptom of which is fluttering flight of the disc. Too tall throws stall the disc fighting in vain against gravity also increasing drag of the disc. To get the discs to keep up speed one needs to pull the disc at a constant height and release it at the same height as you pul it back. And pushing the hand down at the wrist to make the disc parallel with the forearm bones.
Youtube disc golf instructional videos help too and you can ask for guidance from players you meet. Disc golfers are often a helpful friendly bunch. Slow motion videos are especially helpful in copying ideas from other players and there are many styles. Check out double angle and comparison videos in slow motion on Youtube on the channel mfranssila and embedded in some earlier videos at lcgm8 mainly Tali Open videos and a video called seven drives with Avery Jenkins.
A pitcher should have a nice forehand throw and there is a European champion that is forehand dominant with baseball background. Grip makes a world of difference in sidearm throws and for help on that go to http://www.discraft.com
and check their videos for a sidearm clinic that Mark Ellis on this forum is the host of. My grip tip is to have lots of grip pressure and tucking in the disc as deep into the hand as possible for a little power loss and a lot of accuracy and consistency gain.
Enjoy yourselves and don't forget to ask for help. Unlike golf disc golfers are eager to help as long as they are not in a hurry or training for competition more often than not. Frisbee spirit is very welcoming.
Flat shots need running on the center line of the tee and planting each step on the center line. Anhyzer needs running from rear right to front left with the plant step hitting the ground to the left of the line you're running on. Hyzer is the mirror of that.