Is a job offer letter sent and accepted by email legally binding?

I am considering accepting this job offer but am in the interview process with another company that I should hear back from soon. This current offer is for a 3-month contract and the one I am waiting on for is a Full-Time position. My question is: If I accept this job offer via email, is it legally binding in case I want to rescind the acceptance if I get the better job? The email offer I received is below:

Hello [Me], Great news. [Manager] would like to offer you for [job role] while we are pending the reference checks. As they do not want to lose you while we wait. Manager: [Manager Name] Start date: 5/3/2021 Once you accept the offer, please confirm the following details: Are you able to start on the start date listed above: Do you have time off already planned in the first 90 days of employment?: Do you prefer a PC or Mac: Your complete Address for shipment: Phone number: Personal Email: Reply awaited, [Recruiting Manager]

There is no place to sign and I am curious if accepting this offer via email before receiving additional documentation to sign or beginning the actual job/onboarding process is legally binding in any way in case it's better for me to back out and take the other job (if I get it). They said they needed the response by this afternoon, but I did send an email asking for more time to consider accepting the offer. As of right now, I haven't heard back from them on this extension. I've been out of work due to Covid and need a new job, but I'd hate to be locked in to a 3 month position only to go through this again when there's the possibility of a better position just on the horizon. Any help sorting this out would be appreciated. Thanks!