Welcome to the site !!
To be honest , you cant go wrong with a Dunlop MX33 Soft/Intermediate , it is the main tire I use after the original tire wore out quickly , I use it for sand , loam , hard pack , wet , or dry dirt , it actually works very well in just about all soil types and conditions , and it lasts forever , .... the tire you listed is not the model of the tire , All Dunlop are Geomax , the designation would be like MX3S , or MX53 or MX33 , or AT81 , so look for something like that on the tire , that will tell you what you have , it will usually be 2 letters followed by 2 numbers , like my examples above ......
My 2020 450R came stock with a MX3S , and it was sketchy at best , I had zero confidence in that tire after the "new" wore off in about 3 hours , then it was dangerous to try to go fast without feeling like you were going to lose the front end , or just crash at any moment , especially in corners , it was toast and worn down and rounded in about 10 hours , I have had the MX33 on there since , it has 64.3 hours on the bike and all but 10 of those hours is on the MX33 , it is my go to tire for just about anywhere , prior to that I preferred the Michelin Starcross Medium on my old bike , but this Dunlop outlasts and tractions it by a long shot .... if I go to a real deep sandy track , I sometimes use a Michelin Starcross 5 Soft , but the MX33 I can really use everywhere without worries about traction or wear , I ride pretty much every weekend or more if I can , and the track where I ride will put any tire to the test , it is a mixture of clay , sand and hard pack , with square edge holes , loose powder , deep sand , sometimes wet , usually dry , and rough , with G-outs and off camber areas , and this is by far the best tire I have used period in the 12 years I have been riding at this track , I would not hesitate to go to any track anywhere with that tire regardless of the soil type or conditions .
Hopefully that helps give you some guidance ....

..... Oh , and I am going on 62 in a couple months , and I was away for several years myself from the late 70's to around 2005 due to a broken back (3 times , but only once from riding and that was on the street , the other 2 were work related) , then came back , and got seriously injured , was off for another year healing and rehabbing (broken neck 09), came back , got injured again (broken wrist 2016) and dealing with other serious medical conditions (heart attack ,cancer, and a few other issues 2017/18) , and have not stopped riding since , I am almost back up to speed again

..... Advice ... Don't try to keep up with the guys that have been riding all along , do what you feel comfortable doing and work your way up , you will get it back up to speed and confidence , but let it come to you , don't force it , or it will bite you hard ... Trust me on this ... and wear a pile of protective gear (body armor that covers my Back , Chest , Shoulders , Elbows ,Forearms ,Kidney Belt , knee guards , wrist braces and oddly no neck brace because it restricts my minimal neck movement too much) ... Dress to crash and try not to ...
