Here are Some easy to intermediate codeforces graph/backtracking problems this problems normally only use some basic knowledge of graphs/trees + basic algorithms , I hope it helps
1-Destroying Bridges 1944A - Destroying Bridges rate : 800 -> basic of graphs [Very Simple]
2-Computer Game 1598A - Computer Game rate : 800 -> not so much graph [Very Simple]
3-Li Hua and Maze 1797A - Li Hua and Maze rate : 800 -> not so much graph + edge cases [Very Simple]
Sum in binary tree 1843C - Sum in Binary Tree rate : 800 -> not so much graph or tree [Very Simple]
Love triangle 939A - Love Triangle rate : 800 -> can be solved with graph or not [Very Simple]
Party 115A - Party and Party 116C - Party rate : 900 -> bfs [Simple]
New Year Transportation 500A - New Year Transportation rate : 1000 -> dfs [Simple]
Transformation : from A to B 727A - Transformation: from A to B rate : 1000 -> backtracking / dfs [Simple]
Badge 1020B - Badge rate : 1000 -> dfs [Simple]
Frog Jumps 1324C - Frog Jumps rate : 1100 -> not so much graph but can be solved with dfs [Very Simple]
Dzy loves chessboard 445A - DZY Loves Chessboard rate : 1200 -> can be solved with dfs [Simple(simpler than it's rating)]
Ice Skating 217A - Ice Skating rate : 1200 -> dfs [Simple/Intermediate]
Rumor 893C - Rumor rate : 1300 -> dfs [Simple]
Dreamon and Wifi 416B - Art Union rate : 1300 -> backtracking [Simple]
4-Inversion Graph 1638C - Inversion Graph rate : 1300 -> creativity [Simple/Intermediate]
Game On Tree 1970C1 - Game on Tree (Easy) rate : 1300 -> trees + dfs/bfs [Simple/Intermediate]
5-Queen 1143C - Queen rate : 1400 -> trees + you can use dfs/bfs [Simple]
Two Buttons 520B - Two Buttons rate : 1400 -> bfs [Simple/Intermediate]
6-Kefa and park 580C - Kefa and Park rate : 1500 -> trees + dfs/bfs [Intermediate]
7-Cyclic components 977E - Cyclic Components rate : 1500 -> dfs [Intermediate]
Maze 377A - Maze rate : 1600 -> bfs [Intermediate]
The Two Routes 601A - The Two Routes rate : 1600 -> bfs / matrix [Intermediate/Hard]
Graph Without Long Directed Path 1144F - Graph Without Long Directed Paths rate : 1700 -> bipartite graphs [Intermediate/Hard]
Beautiful Graph 1093D - Beautiful Graph rate : 1700 -> bipartite graphs [Intermediate/Hard]
Game On Tree 1970C2 - Game on Tree (Medium) rate : 1700 -> a little hard + dfs/bfs [Intermediate/Hard]