Rashford had a forgettable 2021/2022 season, scoring just four goals in 25 Premier League matches.
The 24-year-old did not look his usual self leading to suggestions his off-field activities, which includes campaigns against child food poverty, were having a negative impact on his output on the field.
Manchester United eventually finished sixth in the Premier League after replacing Ole Gunnar Solskjaer with Ralph Rangnick and Rashford has since lost his place in Gareth Southgate's England squad.
Rashford has fared better at the start of the current campaign, scoring three goals in six league matches so far and has been nominated for the Premier League's player of the month for August.
Cole believes Rashford has benefited from getting back to basics and could even sneak a spot when Southgate finalises his squad for Qatar.
"It's nice to see [Rashford doing well]," Cole told United's official website. "He's got the confidence back, [and] scoring goals. I think he'll be really happy with that.
"If he can propel Manchester United forward this season, gets us into – I'm not sure what position we are going to end up in exactly, but if we can finish in the top four, it'll be good.
"It's the first time we've seen Marcus run in behind and stretch teams since he first got into the first team.
"I think he went away from his strengths [last season], which was stretching teams.
"If you look at how he's playing now to when he first got into the team, people will turn around and say, 'that's the Marcus Rashford of old.'
"If he sticks to that, he'll score goals."
"You'd believe that [he can play for England in Qatar this year]," he added. "But I think the only person you can ask about the World Cup squad is [Gareth Southgate].
"Your bread and butter is always your club football, and if you do well for them, you've always got a chance."
