Is there a file size limitation?

Yes, there are some file size limitations in SharePoint.

Details

Maximum upload size for a document in a library

• SharePoint on premises prior to SharePoint 2016: 2 gigabytes
• SharePoint 2016: 10 gigabytes
• SharePoint 2019: 15 gigabytes
• Office 365: 100 gigabytes in Normal mode, 15 gigabytes in Insane mode.

Note: For SharePoint on premises, the maximum upload size can be lowered or increased in your web application's settings. In Office 365, that limit cannot be changed.

Maximum upload size for a list item attachment

• SharePoint on premises: 50 megabytes
• Office 365: 250 megabytes

Note: For SharePoint on premises, the maximum upload size for list item attachments can be modified. In Office 365, that limit cannot be changed.

Insane mode on-premises packages your information in order to increase the migration speed. For example, Sharegate packages list items and sends all the attachments and metadata along your list items. This means the size limitation now applies to the entire package and not to a single element as per usual.