Welcome!! Here are my go to spots that are great for getting started.
1) Prosper Town Lake: Small lake, good fishing and no power boats allowed.
2) South Lake in Farmersville: Another small lake with good fishing and no power boats.
3) Elm Fork of the Trinity: This is the stretch of water that runs from Ray Roberts Dam to Lake Lewisville. You can launch from the middle park located off 428 or from the park located at Lake Ray Roberts. I prefer launching at 428. This way I can fish North and South.
These would be my top 3. I fish with my 14 year old daughter so I am only looking for the safest areas for her.