Q. Word automatically keeps indenting my paragraphs.

When this is happening in one document, this is a setting that you’ll find under paragraph. To access and change it:

1. Right click your curser and select Paragraph form the pop-up menu.
2. In the resulting Paragraph box, look under Indentation.
3. Use the pull down menu to select Special, it probably has First line selected.
4. Change it to (none) and hit ok. That's it! You should be back to normal.

If this keeps happening in all your documents, it may be associated with the style used in your default template. Per Microsoft, you can change this by:

1. On the File tab, click Open.
2. Go to C:\Users\user name\AppData\Roaming\Microsoft\Templates.
3. Open the Normal template (Normal.dotm).
4. Make any changes that you want to the fonts, margins, spacing, and other settings. You can use the same commands and features that you use to change a document — but remember that any changes that you make to Normal.dotm will be applied to documents that you create in the future.
5. When you have finished, click the File tab, and then click Save.

https://support.microsoft.com/en-us/office/change-the-normal-template-normal-dotm-06de294b-d216-47f6-ab77-ccb5166f98ea