A few questions about Git in a team?

Question

git

Greetings.
In our team:

• 2 backend developers
  
• 2 full stack developers
  
• 1 frontend developer
  
• 2 junior frontend developers
  

We use Bitbucket, private repositories, where each repository is a project.
There are usually 2 branches in the repository - master and dev, master is on the battlefield, backend and frontend developers work in dev.
So far, there have been no very difficult situations with conflicts, but even minor conflicts have to be resolved for a long time, since everything is remote, and the juniors do not understand how and what to solve (little experience).
The process of work and deployment now looks like this:
1) work in the dev branch
2) push to dev
3) someone logs into the server via ssh and does the following:
-> git checkout dev
-> git pull origin dev
-> git checkout master
- > git mergedev
At the same time, the branch in bitbucket master may not be updated for a month, and everything flies for 10-15 seconds during the battle, since the dev branch is standing, not master.
Tell me approaches for work or what we need to change (and how, if possible)?