How to create a barplot of counts for multiple variables

Question

I have an excel sheet similar to the example below but with many rows and columns.

ID	HT	Stroke	HT follow up	Stroke follow up
1	No	No	Yes	No
2	Yes	No	No	No
3	Missing	Yes	Missing	No

HT refers to hypertension. I wanted to create a barplot showing the number of rows with "no" or "missing" for HT, and the number of rows with "yes" or "missing" for HT follow up. The y axis would be the number of counts and the x axis would be divided into two parts; ht and ht follow up, each part with two bars. What i did so far was create a dataset with the columns id, ht, and ht follow up. This dataset has the rows filtered to have ht rows that are either "no" or "filtered", and ht follow up rows that are either "yes" or "missing".

ht=exceldata[,c('id','HT','HTFU')]
ht1=subset(ht, HT=="No"|HT=="Missing")
ht2=subset(ht1,HTFU=="Yes"|HTFU=="Missing")

Any help would be appreciated!