The simple and continuous forms of all verbs have their respective nuances and you should decide what you want the sentence to mean, and then choose the appropriate form:
All simple forms of the verb indicate an action as a whole - from start to finish.
The simple form of the verb can indicate a habitual or regular action that
(i) is/was/will be complete/completed each time it is undertaken.
A: What do you do to keep fit?
B: I ride a bike. -> “ride” includes everything from getting on the bike at the start of the journey to getting off the bike at the end.
Or
(ii) a single, complete or completed present, future, or past action:
"He told me that I had to visit the Eiffel Tower, so I go/went/will go to Paris on Wednesday” -> “go/went/will go” includes everything from the decision being made, bags being packed, going to the airport, etc., to the arrival in Paris.
(iii) a habitual, recurring, regular or frequent action (that is completed each time)
On Saturdays, I go to the gym.
He ate toast for breakfast every day of his life.
NB the to infinitive verb (He went to the river to swim) often is a short form of “in order to do something”. in order to verb - so that subject experiences the completed action of the verb.
The continuous form of the verb indicates
(i) an action that is/was/will be (a) incomplete and (b) in progress (c) at the time that is being referred to (it has started but it has not yet finished) -> I will be/am/was/have been/had been riding a bike = I will be/am/was/have been/had been in the process of riding a bike but have not yet finished riding the bike at the time I am referring to.
The continuous form, particularly in the past, used to be known as “the imperfect”: It was called “imperfect”* because the action had not been “perfected” i.e. it had not finished.
Another feature of the continuous form is that it allows the action of one verb to take place inside another:
He sang the song and ate the apple. – two distinct actions
He was singing the song and eating the apple – one action, singing, inside another, eating.
The distinction between to simple and the continuous (often, but not always, aided by context) can be seen in
“He pointed to a man and said ‘That’s John’.”
Here, it is unclear when or if he stopped pointing; the assumption is that he pointed, stopped pointing, and then spoke.
“He was pointing to a man and said ‘That’s John’.” –
he was pointing and then spoke.
“He was pointing to a man and saying ‘That’s John’.” –
he was both pointing and continuously saying ‘That’s John’.
*
OED 5. Grammar. Applied to a tense which denotes action going on but not completed; usually [my edit: - but not always] to the past tense of incomplete or progressive action.
1871 H. J. Roby Gram. Latin Lang. §549 Three [tenses] denoting incomplete action; the Present, Future, and Imperfect (sometimes called respectively, present imperfect, future imperfect, past imperfect).
