Well if you say you must be getting old because you enjoy being outside gardening then I must be 200 years old by that metric since I have been gardening since I was a small child :P

For the carrots I recommend either raised beds or directly in the ground in rows. After they will come up around or before midsummer you might want to do some thinning since the carrot seeds are small and it is hard to space them out sowing by hand. Meaning, you need to go over the row and thin them out (culling some of the seedlings as mean as it might seem) 3-5 centimeters apart for each tiny seedling. This will ensure your carrots will have growing space to develop full size. That is one of the biggest mistakes I see people do. Not thinning the seedlings and ending up with carrots that are each smaller than a human finger.

I make to do lists for everything. My memory is getting worse past few years.