[Nitesh]

Well i have done many project on configuration outlook account with salesforce , Refer this Blog : https://cloudanalogy.com/blog/microsoft-office-outlook-salesforce-configuration/

[Nitesh]

Hi Ram
First you need to know what is Theming?
Theming brings about a transformation in the look and feel of a Salesforce Community. It helps to bring a much deeper level of customization. In fact, theming may offer a hierarchical problem, as it becomes complex by using dynamic components,  components written by other users for the App Exchange — as well as page level variations.
Do check this link for more information about Theming
https://cloudanalogy.com/blog/build-and-import-customized-personalized-content-into-communities/
Hope it help!!
Thanks

[Nitesh]

MODEL
The model is your database objects in Salesforce. The include the standard Salesforce objects like Leads, Contacts, Accounts, Opportunities etc but it also includes any custom objects you've created.

VIEW
The view represents the presentation of the data (i.e. the user interface).

Pages - While often just called "pages", what we are talking about is Visualforce pages. They are the building blocks of the user interface. Visualforce uses HTML to lay out the appearance of the application interface. Each page is referenced by a unique URL just like a regular webpage. The pages themselves also contain Visualforce Components which can be invoked by simple tags inside the page.

Components - these are both standard and custom Visualforce Components. Think of them like widgets that you can add to your pages. Once you write the code once, you can reuse it on multiple pages. Components are important because they allow for this reuse. Components can be styled with CSS.

CONTROLLER
Controllers are the building blocks of the actual application logic. The controllers are written in Apex code and they end up controlling and enforcing all the business logic.

[Nitesh]

we can add customs filed to a standard and their Custom object in salesforce Technology that allowing you to infinitely customize Organization
Available in Both salesforce Classic and lighting experience.

[Nitesh]

Do the unit Testing
Do the code review
Always write the test case according to your Project and follow that test case.
Follow the SDLC model of testing.