Gyms can be used for showering, wifi, using the restroom, and even exercising if you are so inclined. No one will look at you funny if you just use the showers.
Ideally you will be able to access a gym associated with your workplace or school for free; be sure to ask if one is available. If not you can get a subscription to a commercial gym like Planet Fitness, Anytime Fitness, 24 Hour Fitness, etc. In some areas the local rec center or YMCA may be cheaper.
Planet Fitness is the most commonly-used commercial gym. There are two kids of membership:
standard - ~$10/month plus annual membership fee. This would be sufficient for people who stay in one area.
Black Card - ~$22/mo plus annual membership fee. The most important benefit of the higher-priced subscription is the ability to use PF gyms nationwide. It also includes access to hydromassage beds, massage chairs, etc. Black Card members can bring one guest per visit, which might be advantageous for couples traveling together.
Things to be aware of:
While some PF in bigger markets are 24/7, in smaller markets they may be 24/5 with some hours of closure on the weekends when attendance is low. Check the gym's website for hours of operation.
PF makes it difficult to cancel a subscription. Generally speaking it needs to be done in person at the Home Gym or by certified letter. See note below about Home Gyms.
Black Card use of non-home gyms is restricted to 10 days to the same non-home gym a month: “Reciprocal access is limited to 10 visits per month to a visiting location. Additional fees may apply if you exceed 10 visits to the same visiting club
in a month.” (emphasis
added). One reading of this is if there are ≥3 non-home PF in the area (or 2 non-home + the home gym) one could rotate between them without bumping into the limit.1)
If one will be in one spot for a long while the home gym can be transferred from the account page
Black Card guests will have to sign in for each visit, and typically cannot use the hydromassage or other Black Card amenities.
One reading of this is if there are ≥3 non-home PF in the area (or 2 non-home + the home gym) one could rotate between them without bumping into the limit.2)
If one will be in one spot for a long while the home gym can be https://join.planetfitness.com/transfer/Step1.aspx