Having 10 years of experience. Working in MNC company.
First will java and once comfortable in core java. I will move you to on Selenium testing.
In core Java
1. Classes
2. Loop
3. Calling classes by object
4. File handling.
5. Inheritance
6. Polymorphism
7. Abstraction
8. Collections etc
After comfortable on above I will start selenium.
1. Webdriver
2. Initiation of different browser.
3.first selenium script example of login page.
4. Element identification on webpage.
5. I'd
6. Xpath
7.Tagname
8. Claasname
9.linkText
10.name
Generic xpath creation. Use of following and preceding. Will create xpath in such a way so if there is any changes in table structure of webpage so xpath should not fail. Will induce variable in xpath to make it generic.
11. PageObject Model: in this we will put elements in java class as well as in XLS file. So if any changes in xpath will just need to go in one place and no need to here and there in code.
12. GIT
13 MAVEN
14. JENKINS