Help needed on Fixing replication latency issues

Hi Team,
Good day!!!
I am new to replication setup and I am working on the issues with replication latency.
Can you please provide us your experience and expertise on fixing and troubleshooting replication issues.
Below are some queries on that,

1) How to check the replication errors?
2) how to find out the replication latency?
3) What are the steps to fix the replication latency?
4) how to teoubleshoot the issues coming on replication latency?

Awaiting your valuable response and replies.

Thanks in advance,
Sarvan.N