Go for TOEFL.
If you've been preparing for GMAT the reading section will be a walk in the park.
ETS has also uploaded some free practice sets and resources on their site for TOEFL Preparation, they are more than enough.
As for the other sections, practice a few questions from the official TOEFL channel on YouTube.
Link to the playlist I used -
https://www.youtube.com/playlist?list=P ... C34BF71B4CThere is a 60-minute video from this channel called "The Urban Fight" on YouTube that you can check out -
https://www.youtube.com/watch?v=7XA49rW ... e=youtu.beNotefull is another YouTube Channel you can check out
I had about 3-4 days of time to prepare and managed a score of 108/120 (Reading - 27/30, Listening - 28/30, Speaking - 29/30, Writing - 24/30).
I gave my test on November 20, 2022.
I did not practice writing much and exceeded the word limit in the final test too.
Would suggest that you practice as many questions as you can.
Cannot comment on IELTS but it is probably going to be similar in terms of the difficulty of the questions.
P. S. - It is my personal opinion that you don't need to do any course for TOEFL.
Hope this helps, best of luck!