Can I use 61W macbook charger

No problem.

See these support articles:--> Charge your iPhone with an iPad or Mac notebook power adapter - Apple Support

and/or:--> Fast charge your iPhone - Apple Support

Regards

Giulio

You can use it but it will not be as fast as Apple's 20 watt charger.

61watts will be a bit faster than the 20watts adapter , and no, it will not damage the phone.

You and Kirk need to coordinate your answers 😏

Lawrence Finch wrote:

You and Kirk need to coordinate your answers 😏

😅