Questions about getting an extension and efiling after 4/15/25

I never did this before.

 

It looks like TT creates a mail in form to put in for an extension (not electronic) ?

 

If you do (or even if you do not) apply for an extension, can you still efile Federal & NJ State returns AFTER 4/15/25? 

 

Or are ALL returns after 4/15/25 mail-in only?