Taxpayer is deceased 2022. He is single dad (unmarried)

The mom possessed Death of Certificate and arranged all his funeral expenses 

Can the mom file his tax return with form 1310 (statement of person claiming refund) electronic?. No court appointed doc and no spouse and no will.

Can filer (mom) request taxpayer's refund Direct deposit in her 's bank?

If IRS and state issued refund paper check, then what the mom can do to cash out? Or can his children cash out?

Appreciate your advice and sharing info