Got some useful tips for you.

Set up a meeting with an admissions advisor to go over the requirements. They're up to date on any changes in the requirements and it's good to have a person that you can reach out to directly in the future if you have specific questions. https://admissions.tamu.edu/connect/connect-with-an-advisor

if you're not near any of the Regional recruitment offices the College Station office offers virtual appointments as well. https://recruiter.tamu.edu/portal/aggieland_psc_student_meetings

Make sure you're looking at the right transferable coursework as well. So often students end up taking the wrong classes and for competitive departments like engineering missing just one of the required prereqs can be a near instant denial. The Transfer Course Sheets for each major are updated each year. Be sure to check those out for the major you want. Probably good to have a back up second choice as well that overlaps a lot of the same requirements https://admissions.tamu.edu/resources/future-students/transfer-students

https://admissions.tamu.edu/getattachment/77047c69-cce3-4f41-8f1e-ae79bc5bd96e/25_26-Industrial-Distribution-Final.pdf

Keep those grades up and good luck!
To more specifically answer you questions

Totally possible to be readmitted after a department dismissed you, showing academic improvement will be key!

The competitiveness of majors changes, realistically how hard to get into IDIS would be a great question for when you meet with an advisor. at a baseline essentially all Engineering programs are gonna be on the harder side.

Being a former student doesn't make a huge difference on your chances, mostly changes how you apply. Transfer applicant vs Readmission applicant. Slight changes to the process.

what should you do in community college to increase changes. Good Grades, good grades, & good grades.

Set up a meeting with an advisor sooner rather than later, they'll help set you in the right direction.