You can train strength and mass at the same time. Just train a movement for strength first, then fill in the rest of your day with “bodybuilding” type stuff.
An easy template to follow would be 5/3/1 by Jim Wendler. I would recommend buying the book, it has a lot very useful info for any lifter and how the program works specifically. Do some research on your end and you will find plenty of information. There are many, many varied templates in the book depending on your goal. A simple template that requires really just a barbell and a rack would be the 5x10 work. A sample day would look like this:
As far as diet, the simpler the better. If you have access to meat, vegetables, rice, potatoes, and things like that-- you’re good to go. Just eat 3-4 meals consisting of the items I just mentioned, lift heavy and with intensity… and you will be good to go. If you wanted to, you could also start walking every day for about 30-45 minutes, doing some jogs up a hill, or something like that.