$ git init

$ echo hello>hello1.txt

$ git add .

$ git commit -m 'initial commit'

$ git branch feature

$ git branch bugfix

$ git branch
bugfix
feature
* master

$ echo second>>second.txt

$ git add .

$ git commit -m 'second.txt'

$ git switch feature

$ echo third>third.txt

$ git add .

$ git commit -m 'third'

$ git switch bugfix

$ echo four>four.txt

$ git add .

$ git commit -m 'four.txt'

$ git switch master

$ git log --oneline --graph --all
* f5c8a8f (bugfix) four.txt
| * 97520af (feature) third
|/
| * 075d9c2 (HEAD -> master) second.txt
|/
* dcd8e55 initial commit

Check status of the merged and not merged branches from master using option --merged and --no-merged. 
The output it is clear that the branches bugfix and feature are to be merged to the master branch.

$ git branch --merged
* master

$ git branch --no-merged
bugfix
feature

Merge the feature branch to the master branch and check the merged and unmerged status of the branches.

$ git merge feature
Merge made by the 'recursive' strategy. 
third.txt | 1 +
1 file changed, 1 insertion(+)
create mode 100644 third.txt

$ git branch --merged
feature
* master

$ git branch --no-merged
bugfix


[LINKS]
https://www.tutorialspoint.com/how-to-view-merged-and-unmerged-branches-in-git
