How to grant full access permission to enable add-ins to office AND anything else

Having more context as Jade mentioned is important to understand what happened that led to this stage and what steps then can be taken to rectify the situation.

First can you clarify which business account you subscribed to? I would assume its Microsoft365 business standard?

Second, just to get context, where did you subscribe this plan and how did you reach a MS rep?

Third, can you explain what is working and not working now?

M365 has web, and downloadable MS-Office components.
Can you login to the web version? Does Email, Onedrive for business, Microsoft Teams, Forms etc all these work?

Then the Mac version - were you able to download it and install it?

If you could give more context it will help a lot.

Also on Azure/Entra. Some explanation is needed.
Microsoft needs to store your user information somewhere. Your admin account, your account, the username, passwords etc. This is stored in an app called EntraID, which is running in Azure.

Each M365 Business Subscription requires you to work with Entra ID to

1. Create an administrative account on EntraID, in the form of yyyy @ xxx.onmicrosoft.com
2. Then add a business domain if you want like contoso.com (you will need to verify you own it)
3. Then add users zzzz @ contoso.com
4. Up to this point its free and does not require a license
5. Add the licenses that you purchased.

So done correctly its really your own corporate account in EntraID, running on Azure.

There has been some dubious sellers online, who sell unused subscriptions of their schools or companies, to unsuspecting users who want to only use MS-Office. These come with other people's EntraID domain attached, like Acme.onmicrosoft.com can is tied to their own organizations and can't be changed.

Update us more and lets see how we can help.

Dear Kimberly Steefel,

I’m sorry the initial setup has left your Microsoft 365 environment confusing to manage. Since you are the only user, let’s first confirm your administrator access rather than granting unrestricted permissions.

To start, please sign in to the Microsoft 365 Admin Center, then go to Users > Active users, select your account, and review Manage roles. Please let me know which administrator role is currently assigned to your account.

If you are a Global Admin, you can then check whether access to the Office Store is enabled:

1. In the Microsoft 365 Admin Center, select Show all > Settings > Org settings.
2. Under Services, select User owned apps and services.
3. Make sure Let users access the Office Store is selected.
4. Select Save.

Once this setting is enabled, you can open Word, Excel, or PowerPoint and use the Add-ins option to browse and install available Office add-ins.

If you want to centrally deploy a specific add-in to your own account instead, go to Microsoft 365 Admin Center > Settings > Integrated apps. During deployment, you can assign the add-in to Just me. If that particular app requires administrator consent, its requested permissions will be displayed during deployment for review.

For more information about installing add-ins from the Microsoft 365 admin center, see Deploy Office Add-ins in the Microsoft 365 admin center.

The Microsoft representative who instructed me on how to set up everything has messed up my entire system (I am a mac user and he did not know mac at all).

Regarding your statement, could you please clarify what was changed or configured during your previous support interaction and what is currently not working as expected? Please also let me know which setup or troubleshooting steps you have already completed and where you are currently experiencing difficulties.

Feel free to correct me if I have misunderstood any part of your concern. I look forward to hearing from you, and I truly appreciate your time and contribution.