OK it is very intense, but i really really loved doing it. I was not prepared enough for the sheer amount of homework, written work that it required.
I can highly recommend it though - if you are already a teacher you have a head start on me. Not sure how they do it with the online courses, but we spent mornings in the classroom learning how to TEFL, and the afternoons teaching actual students.
For us we were divided into 2 arbitrary groups of 6 (max 12 on the course) and we spent 2 weeks teaching the beginners, and 2 weeks teaching the intermediates. Starting at about a 10 minute lesson each. Then we were graded on our skills. (so preparation, engagement with students, and as little Teacher Talking Time as possible)
I am still great friends with the people i did my course with too. So - all in all, deffo worth a try, but as i said beware of those online courses that advertise "120 hours" because they are deffo making out they are as good as the CELTA, and they deffo are not.
But as i said up there, i would first look around language schools and see what they are looking for in a teacher? tbh the first time i taught English was a side hustle on Maternity Leave - and i had no qualifications at all aside of being a native speaker and not entirely dim. You never know, they may take you on and sponsor your CELTA to some degree?