First computer hex-based wargame I played was on my TRS-80 back in 81
https://en.wikipedia.org/wiki/Tankti..._Eastern_Front
You got a hex map and punch out units, spend 20 minutes loading it up off the tape cassette and then had to shuffle
both sides counters!.
There also was a simple battle of Midway one where the enemy fleet was a "F" or a "B" on a grid on screen. At least that one did not need paper shuffling
. Only air strikes were counted - if the Japanese invasion fleet coincided with your "E" for Enterprise task force then there was no surface action.
Both were in TRS-80 BASIC so you could look at the source and make edited versions. Nobody bothered, though. I think those games were Avalon Hill ones.
Price was ~25 pounds, when a pound would buy 2 pints in the students union. 50 pints at (say) 4 quid today = £200 in today's money. The basic 4K TRS-80 cost about 250-300 pounds as I recall. My first 5 1/4" floppy disk drive for it was another 300 pounds or so in 1982-ish. Early computer kit was not cheap.
The college mainframe was a Dec-20 and after 6PM I think, made games available. It had Star Trek, Rogue, some text-only dungeon, and Empire. Empire was hugely addictive - you built tanks and ships in your one starting city and went off exploring and conquering the world!. Empire would later appear a decade or so later with fancy graphics as "Civilisation".