How do you fix Word's project gallery from Spanish to English?

The language setting affects only the language of the text you write. The language of the version of Office is determined by which package you purchased. If you purchased a Spanish edition of Microsoft Office, the entire interface include templates and Project Gallery will be in Spanish. You would need to obtain and install the English language version of Microsoft Office to have everything in English (don't try to install both versions at once on the same computer - remove the one you're not going to use before installing the other one). You don't actually need to purchase a second copy of Office, as your product key will work with either Spanish or English versions - but you must uninstall the language you are not going to use before installing the one you are going to use.