I have some questions

I'm thinking about trying a vegetarian diet. Mostly for health reasons. I've been doing a Daniel fast for religious purposes. It's essentially a vegetarian diet. anyways I have always had stomach issues. Gastritis / acid reflux. Within the past year I've noticed that red meat and my stomach don't agree any more. Gives me horrible gas and just makes me feel terrible. Anyways I'm on day six and have noticed some differences. The only negatives have been some bloating and I've been urinating alot. Probably because I've been eating a lot of veggies and fruit which are mostly water. Anyways how careful do you have monitor protein/ fat intake? I'm like 6 2 and 225 currently. A healthier weight would probably be 215. I weight lift so I have some decent muscle but could probably lose some flab. So you need to track it? Or just be intentional about making sure to eat beans/lentils/ nuts ect