Installation is usually just copying the app to your Application folder. If it is a PKG, then there is an installation process.

The HDD icon is probably just the DMG that you mounted. You can dismount it after installing/copying it.

1. Download PSI
2. Open the DMG
3. Open up your App folder
4. Drag PSI to the your App folder
5. Unmount PSI
6. Go to your App folder and run PSI

If you don't see PSI in your App folder, you didn't manage to put it there correctly.

To uninstall, drag PSI from App folder to your trash.

There are little to no "portable apps" for MacOS.

I don't use Safari often, should be OK. You can use Chrome or FireFox web browsers for saving login passwords. Just download from their website.

I have install Bitwarden but hardly use it  .

What you use on Windows ? Probably already available on Mac.

U will eventually learn how the OS works. One of the method is what u are doing now, asking questions. We will help as much as we can.

To use multiple OS is great. Be it windows or mac or linux.

Anyway u can install Parallels Desktop and run windows together with ur mac given the app is not available for mac.

Show desktop? If u using macbook pro, u can set ur trackpad 3 or 4 fingers gesture in settings.

To open an app downloaded from the net, after install just right click and click open.

Parallels not that heavy, just be sure to set the correct hardware value according to ur usage when install, RAM/CPU/STORAGE.

Show desktop? If u using macbook pro, u can set ur trackpad 3 or 4 fingers gesture in settings.

To open an app downloaded from the net, after install just right click and click open.

Parallels not that heavy, just be sure to set the correct hardware value according to ur usage when install, RAM/CPU/STORAGE.

You can set a shortcut for it under Settings > Trackpad > More Gestures > Show desktop

Like previous forumer mentioned, you can actually dual boot ur Mac to have both Windows and MacOS.

Just buy the software called Parallels. Then you can install windows on your mac

Then you have no choice but to have 2 different machines 

What files are those? Cant it be transferred over to the Mac?

U can install microsoft office in macs.

U can run windows simultaneously with mac. Parallels or any virtual machine app enable u to do that.

what do u mean not allowed? boss wont let u install microsoft office?

errr why....? numbers only work on mac. excel works on both platform.

well, if thats the case u might wanna learn how to use numbers to create spreadsheet then. get used to it and u will know how it works in no time

use windows before and suddenly forced to use macOS

I think it's pretty safe. I'm using for years without any issues.
It will prompt you for more stronger password or reusable of same password.
If you using other Apple devices you password will automatically sync via iCloud.
You can can try MacPass. A free, open-source, KeePass-compatible password manager for macOS.

1. Click MacPass-0.7.9.zip to download app.
2. Open Finder and go to Downloads.
2. Double click downloaded MacPass-0.7.9.zip to unzip it.
3. Copy MacPass to Applications.
4. Done ready for use.